View Filing Data

Loss on sale of property, plant and equipment

144

143

169

Deferred tax provision

(25)

(2)

(51)

Impairment charges

Other non-cash (income) charges, net

^[1]

(8)

(7)

(5)

Non-cash compensation

(3)

(5)

Changes in assets and liabilities:

Accounts and notes receivable

(111)

(116)

215

Inventories

(79)

(7)

184

Prepaid expenses and other current assets

(17)

(18)

Accounts payable and accrued liabilities

(43)

Income taxes payable

(15)

Other liabilities

(12)

(7)

(26)

Cash dividends received from equity affiliates

Cash provided by operating activities

(1)

195

249

399

Cash Flows from Investing Activities:

Additions to property, plant and equipment

(230)

(108)

(106)

Investment in equity affiliate

(2)

(3)

Acquisition of business, net of cash acquired

(5)

Proceeds from sales of property, plant and equipment

(Increase) decrease in assets held for rent

(6)

Settlement of derivatives

(7)

Cash used in investing activities

(232)

(112)

(105)

Cash Flows from Financing Activities:

Borrowings under financing arrangements

Repayments under financing arrangements

(45)

(31)

(69)

Proceeds from long-term debt, net of issuance costs

312

Repayments of long-term debt

(21)

(6)

(321)

Increase (decrease) in notes payable to banks, net

(8)

(16)

Purchases of common stock

(59)

(5)

(2)

Proceeds from sales of common stock

Cash dividends paid to noncontrolling interests

(12)

(6)

(9)

Cash dividends paid to common stockholders

(47)

(48)

Proceeds from restricted stock loan payments

Cash used in financing activities

(72)

(57)

(127)

Effect of exchange rate changes on cash

(Decrease) increase in cash and cash equivalents

(101)

175

Cash and cash equivalents at beginning of period

387

304

129

Cash and cash equivalents at end of period

286

387

304

Income taxes paid

Interest paid

$ 28

$ 24

Non-cash additions to property, plant and equipment

$ 14

[1]	Equity in net income of affiliated companies is included in segment EBIT and is removed from Unallocated and other to reconcile to income (loss) from operations before taxes.

Consolidated Statement Of Changes In Stockholders' Equity And Comprehensive Income (Loss) - USD ($) shares in Thousands, $ in Millions	Common Stock, Net Of Treasury Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Deferred Employee Benefits [Member]	Notes Receivable For Restricted Stock [Member]	Accumulated Other Comprehensive Income [Member]	Cabot Corporation Stockholders' Equity [Member]	Non-Controlling Interests [Member]	Comprehensive Income (Loss) [Member]	Total
Balance, shares at Sep. 30, 2008	65,278
Balance, value at Sep. 30, 2008	$ 61	$ 21	$ 1,143	$ (30)	$ (21)	$ 75	$ 1,249	$ 110		$ 1,359
Net income (loss) attributable to Cabot Corporation			(77)						$ (77)	(77)
Foreign currency translation adjustment, net of tax						22			22
Change in employee benefit plans, net of tax						(36)			(36)
Change in unrealized loss on investments and derivative instruments, net of tax						(1)			(1)
Total other comprehensive income (loss)									(15)
Comprehensive income (loss) attributable to Cabot Corporation							(92)		(92)
Net income attributable to noncontrolling interests, net of tax								2	2	(2)
Comprehensive income attributable to noncontrolling interests									2
Comprehensive income (loss)									(90)	(90)
Noncontrolling interests - dividends								(9)		(9)
Cash dividends paid to common stockholders			(48)				(48)			(48)
Issuance of stock under employee compensation plans, net of forfeitures, shares	172
Issuance of stock under employee compensation plans, net of forfeitures	$ 2	3					5			5
Application of stock option accounting for restricted stock awards		(19)			19
Amortization of share-based compensation		14					14			14
Purchase and retirement of common and treasury stock, shares	(141)
Purchase and retirement of common and treasury stock		(1)					(1)			(1)
Notes receivable for restricted stock-payments and forfeitures					$ 2		2			2
Principal payment by Employee Stock Ownership Plan under guaranteed loan				5			5			5
Balance, shares at Sep. 30, 2009	65,309
Balance, value at Sep. 30, 2009	$ 63	18	1,018	(25)		60	1,134	103		1,237
Net income (loss) attributable to Cabot Corporation			154						154	154
Foreign currency translation adjustment, net of tax						43			43
Change in employee benefit plans, net of tax						(15)			(15)
Total other comprehensive income (loss)									28
Comprehensive income (loss) attributable to Cabot Corporation							182		182
Net income attributable to noncontrolling interests, net of tax								15	15	(15)
Noncontrolling interests - foreign currency adjustment								2	2
Comprehensive income attributable to noncontrolling interests									17
Comprehensive income (loss)									199	199
Noncontrolling interest - other								1		1
Noncontrolling interests - dividends								(6)		(6)
Cash dividends paid to common stockholders			(47)				(47)			(47)
Issuance of stock under employee compensation plans, net of forfeitures, shares	283
Issuance of stock under employee compensation plans, net of forfeitures	$ 1	8					9			9
Amortization of share-based compensation		18					18			18
Purchase and retirement of common and treasury stock, shares	(222)
Purchase and retirement of common and treasury stock	$ (1)	(4)					(5)			(5)
Principal payment by Employee Stock Ownership Plan under guaranteed loan				5			5			5
Notes receivable for restricted stock-payments		6					6			6
Balance, shares at Sep. 30, 2010	65,370
Balance, value at Sep. 30, 2010	$ 63	46	1,125	(20)		88	1,302	115		1,417
Net income (loss) attributable to Cabot Corporation			236						236	236
Foreign currency translation adjustment, net of tax						19			19
Change in unrealized loss on investments and derivative instruments, net of tax						(1)			(1)
Total other comprehensive income (loss)									18
Comprehensive income (loss) attributable to Cabot Corporation							254		254
Net income attributable to noncontrolling interests, net of tax								22	22	(22)
Noncontrolling interests - foreign currency adjustment								3	3
Comprehensive income attributable to noncontrolling interests									25
Comprehensive income (loss)									$ 279	279
Noncontrolling interests - dividends								(11)		(11)
Cash dividends paid to common stockholders			(47)				(47)			(47)
Issuance of stock under employee compensation plans, net of forfeitures, shares	294
Issuance of stock under employee compensation plans, net of forfeitures	$ 1	7					8			8
Amortization of share-based compensation		17					17			17
Purchase and retirement of common and treasury stock, shares	(1,803)
Purchase and retirement of common and treasury stock	$ (1)	(58)					(59)			(59)
Principal payment by Employee Stock Ownership Plan under guaranteed loan				6			6			6
Notes receivable for restricted stock-payments		6					6			6
Balance, shares at Sep. 30, 2011	63,861
Balance, value at Sep. 30, 2011	$ 63	$ 18	$ 1,314	$ (14)		$ 106	$ 1,487	$ 129		$ 1,616

Consolidated Statement Of Changes In Stockholders' Equity And Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Consolidated Statement Of Changes In Stockholders' Equity And Comprehensive Income (Loss)
Foreign currency translation adjustment, tax	$ 3	$ 4	$ 6
Change in employee benefit plans, tax		6	4
Change in unrealized loss on investments and derivative instruments, tax			1
Net income attributable to noncontrolling interests, tax	$ 4	$ 3	$ 1

Significant Accounting Policies

12 Months Ended

Sep. 30, 2011

Significant Accounting Policies

Significant Accounting Policies

Note A. Significant Accounting Policies

The consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States. The significant accounting policies of Cabot Corporation ("Cabot" or "the Company") are described below. Certain changes have been made to operating segment information for prior years to reflect changes made in the fourth quarter of fiscal 2011 related to changes in the Company's reporting segments.

In August 2011, the Company entered into an agreement to sell its Supermetals Business. The applicable assets and liabilities of the business have been classified as held for sale in the Consolidated Balance Sheets as of September 30, 2011 and 2010. Consolidated Statements of Operations for all periods presented have been recast to reflect the presentation of discontinued operations. Unless otherwise indicated, all disclosures and amounts in the Notes to Consolidated Financial Statements relate to the Company's continuing operations.

Principles of Consolidation

The consolidated financial statements include the accounts of Cabot and its wholly-owned subsidiaries and majority-owned and controlled U.S. and non-U.S. subsidiaries. Additionally, Cabot considers consolidation of entities over which control is achieved through means other than voting rights, of which there were none in the periods presented. Intercompany transactions have been eliminated in consolidation.

Cash and Cash Equivalents

Cash equivalents include all highly liquid investments with a maturity of three months or less at date of acquisition. Cabot continually assesses the liquidity of cash and cash equivalents and, as of September 30, 2011, has determined that they are readily convertible to cash.

Inventories

Inventories are stated at the lower of cost or market. The cost of most U.S. inventories is determined using the last-in, first-out ("LIFO") method. The cost of other U.S. and all non-U.S. inventories is determined using the average cost method or the first-in, first-out ("FIFO") method.

Investments

The Company has investments in equity affiliates and marketable securities. As circumstances warrant, all investments are subject to periodic impairment reviews. Unless consolidation is required, investments in equity affiliates, where Cabot generally owns between 20% and 50% of the affiliate, are accounted for using the equity method. Cabot records its share of the equity affiliate's results of operations based on its percentage of ownership of the affiliate. Dividends received from equity affiliates are a return on investment and are recorded as a reduction to the equity investment value.

All investments in marketable securities are classified as available-for-sale and are recorded at fair value with the corresponding unrealized holding gains or losses, net of taxes, recorded as a separate component of other comprehensive income within stockholders' equity. Unrealized losses that are determined to be other-than-temporary, based on current and expected market conditions, are recognized in earnings. The fair value of marketable securities is determined based on quoted market prices at the balance sheet dates. The cost of marketable securities sold is determined by the specific identification method. Short-term investments consist of investments in marketable securities with maturities of one year or less. The Company's investment in marketable securities was immaterial as of both September 30, 2011 and 2010.

Property, Plant and Equipment

Property, plant and equipment are recorded at cost. Depreciation of property, plant and equipment is calculated using the straight-line method over the estimated useful lives. The depreciable lives for buildings, machinery and equipment, and other fixed assets are twenty to twenty-five years, ten to twenty years, and three to twenty-five years, respectively. The cost and accumulated depreciation for property, plant and equipment sold, retired, or otherwise disposed of are removed from the Consolidated Balance Sheets and resulting gains or losses are included in earnings in the Consolidated Statements of Operations. Expenditures for repairs and maintenance are charged to expenses as incurred. Expenditures for major renewals and betterments, which significantly extend the useful lives of existing plant and equipment, are capitalized and depreciated.

Cabot capitalizes interest costs when they are part of the historical cost of acquiring and constructing certain assets that require a period of time to get them ready for their intended use. During fiscal 2011, 2010 and 2009, Cabot capitalized $2 million, $1 million and $4 million of interest costs, respectively. These amounts will be amortized over the life of the related assets.

Goodwill and Other Intangible Assets

Goodwill is comprised of the cost of business acquisitions in excess of the fair value assigned to the net tangible and identifiable intangible assets acquired. Goodwill is not amortized but is reviewed for impairment at least annually. The annual review consists of the comparison of each reporting unit's carrying value to its fair value, which is performed as of March 31. Certain circumstances may give rise to an impairment assessment at a date other than the annual assessment date.

The fair value of a reporting unit is primarily based on discounted estimated future cash flows. The assumptions used to estimate fair value include management's best estimates of future growth rates, operating cash flows, capital expenditures, discount rates and market conditions over an estimate of the remaining operating period at the reporting unit level. If an impairment exists, a loss is recorded to write-down the value of goodwill to its implied fair value.

Cabot's intangible assets are primarily comprised of patented and unpatented technology and other intellectual property. Finite lived intangible assets are amortized over their estimated useful lives. Amortization expense was less than $1 million in each of fiscal 2011, 2010 and 2009.

Assets Held for Rent

Assets held for rent represent cesium formate product in the Specialty Fluids Segment that will be rented to customers in the normal course of business. Assets held for rent are stated at average cost.

Assets Held for Sale

Cabot classifies its long-lived assets as held for sale when management commits to a plan to sell the assets, the assets are ready for immediate sale in their present condition, an active program to locate buyers has been initiated, the sale of the assets is probable and expected to be completed within one year, the assets are marketed at reasonable prices in relation to their fair value and it is unlikely that significant changes will be made to the plan to sell the assets. The Company measures the value of long-lived assets held for sale at the lower of the carrying amount or fair value, less cost to sell.

Assets and liabilities held for sale in the Consolidated Balance Sheets pertain to applicable assets and liabilities of the Supermetals business. See Note C for additional information.

Asset Retirement Obligations

Cabot estimates incremental costs for special handling, removal and disposal of materials that may or will give rise to conditional asset retirement obligations ("AROs") and then discounts the expected costs back to the current year using a credit adjusted risk free rate. Cabot recognizes ARO liabilities and costs when the timing and/or settlement can be reasonably estimated. The ARO reserves were $7 million and $10 million at September 30, 2011 and 2010, respectively.

Impairment of Long-Lived Assets

Cabot's long-lived assets primarily include property, plant and equipment, long-term investments, assets held for rent and sale and intangible assets. The carrying values of long-lived assets are reviewed for impairment whenever events or changes in business circumstances indicate that the carrying amount of an asset may not be recoverable. An asset impairment is recognized when the carrying value of the asset is not recoverable based on the probability-weighted undiscounted estimated future cash flows to be generated by the asset. Cabot's estimates reflect management's assumptions about selling prices, production and sales volumes, costs and market conditions over an estimate of the remaining operating period. If an impairment is indicated, the asset is written down to fair value. If the asset does not have a readily determinable market value, a discounted cash flow model may be used to determine the fair value of the asset. The key inputs to the discounted cash flow would be the same as the undiscounted cash flow noted above, with the addition of the discount rate used. In circumstances when an asset does not have separate identifiable cash flows, an impairment charge is recorded when Cabot is no longer using the asset.

Foreign Currency Translation

The functional currency of the majority of Cabot's foreign subsidiaries is the local currency in which the subsidiary operates. Assets and liabilities of foreign subsidiaries are translated into U.S. dollars at exchange rates in effect at the balance sheet dates. Income and expense items are translated at average monthly exchange rates during the year. Unrealized currency translation adjustments are accumulated as a separate component of other comprehensive income within stockholders' equity.

Realized and unrealized foreign currency gains and losses arising from transactions denominated in currencies other than the subsidiary's functional currency are reflected in earnings with the exception of (i) intercompany transactions considered to be of a long-term investment nature; and (ii) foreign currency borrowings designated as net investment hedges. Gains or losses arising from these transactions are included as a component of other comprehensive income. In fiscal 2011, 2010 and 2009, net foreign currency transaction losses of $6 million, gains of less than $1 million and losses of $15 million, respectively, are included in Other expense in the Consolidated Statement of Operations as part of continuing operations.

Financial Instruments

Cabot's financial instruments consist primarily of cash and cash equivalents, accounts and notes receivable, investments, accounts payable and accrued liabilities, short-term and long-term debt, and derivative instruments. The carrying values of Cabot's financial instruments approximate fair value with the exception of long-term debt that has not been designated as part of a fair value hedge. The non-hedged long-term debt is recorded at amortized cost. The fair values of the Company's financial instruments are based on quoted market prices, if such prices are available. In situations where quoted market prices are not available, the Company relies on valuation models to derive fair value. Such valuation takes into account the ability of the financial counterparty to perform.

Cabot uses derivative financial instruments primarily for purposes of hedging exposures to fluctuations in interest rates and foreign currency exchange rates, which exist as part of its on-going business operations. Cabot does not enter into derivative contracts for speculative purposes, nor does it hold or issue any derivative contracts for trading purposes. All derivatives are recognized on the Consolidated Balance Sheets at fair value. Where Cabot has a legal right to offset derivative settlements under a master netting agreement with a counterparty, derivatives with that counterparty are presented on a net basis. The changes in the fair value of derivatives are recorded in either earnings or Accumulated other comprehensive income, depending on whether or not the instrument is designated as part of a hedge transaction and, if designated as part of a hedge transaction, the type of hedge transaction. The gains or losses on derivative instruments reported in Accumulated other comprehensive income are reclassified to earnings in the period in which earnings are affected by the underlying hedged item. The ineffective portion of all hedges is recognized in earnings during the period in which the ineffectiveness occurs.

In accordance with Cabot's risk management strategy, the Company may enter into certain derivative instruments that may not be designated as hedges for hedge accounting purposes. Although these derivatives are not designated as hedges, the Company believes that such instruments are closely correlated with the underlying exposure, thus managing the associated risk. The Company records in earnings the gains or losses from changes in the fair value of derivative instruments that are not designated as hedges. Cash movements associated with these instruments are presented in the Consolidated Statement of Cash Flows as Cash Flows from Operating Activities because the derivatives are designed to mitigate risk to the Company's cash flow from operations.

Revenue Recognition

Cabot recognizes revenue when persuasive evidence of a sales arrangement exists, delivery has occurred, the sales price is fixed or determinable and collectability is probable. Cabot generally is able to ensure that products meet customer specifications prior to shipment. If the Company is unable to determine that the product has met the specified objective criteria prior to shipment or if title has not transferred because of sales terms, the revenue is considered "unearned" and is deferred until the revenue recognition criteria are met.

Shipping and handling charges related to sales transactions are recorded as revenue when billed to customers or included in the sales price. Shipping and handling costs are included in cost of sales.

The following table shows the relative size of the revenue recognized in each of the Company's reportable segments:


	Years ended September 30
	2011			2010			2009
Core Segment		65	%		63	%		63	%
Performance Segment		29	%		30	%		31	%
New Business Segment		4	%		4	%		3	%
Specialty Fluids Segment		2	%		3	%		3	%

Cabot derives the substantial majority of revenues from the sale of products in the Core and Performance Segments. Revenue from these products is typically recognized when the product is shipped and title and risk of loss have passed to the customer. The Company offers certain customers cash discounts and volume rebates as sales incentives. The discounts and volume rebates are recorded as a reduction in sales at the time revenue is recognized and are estimated based on historical experience and contractual obligations. Cabot periodically reviews the assumptions underlying the estimates of discounts and volume rebates and adjust revenues accordingly.

Revenue in the New Business Segment is typically recognized when the product is shipped and title and risk of loss have passed to the customer. Depending on the nature of the contract with the customer, a portion of the segment's revenue may be recognized using proportional performance.

The majority of the revenue in the Specialty Fluids Segment arises from the rental of cesium formate. This revenue is recognized throughout the rental period based on the contracted rental terms. Customers are also billed and revenue is recognized, typically at the end of the job, for cesium formate product that is not returned. On occasion Cabot also makes sales of cesium formate outside of a rental process and revenue is recognized upon delivery of the fluid.

Accounts and Notes Receivable

Trade receivables are recorded at the invoiced amount and do not bear interest. Trade receivables in China may at certain times be settled with the receipt of bank issued non-interest bearing notes, which represent the Company's notes receivable balance. These notes totaled 380 million Chinese Renminbi ("RMB") ($60 million) and 143 million RMB ($21 million) as of September 30, 2011 and 2010, respectively, and are included in accounts and notes receivable. Cabot periodically sells a portion of the trade receivables in China at a discount and such sales are accounted for as asset sales. The Company does not have any continuing involvement with the notes after the sale. The difference between the proceeds from the sale and the carrying value of the receivables is recognized as a loss on the sale of receivables and is included in other expense in the accompanying Consolidated Statements of Operations. During fiscal 2011, 2010 and 2009, the Company recorded charges of less than a million, $2 million and $1 million, respectively, for the sale of these receivables.

Cabot maintains allowances for doubtful accounts based on an assessment of the collectibility of specific customer accounts, the aging of accounts receivable and other economic information on both an historical and prospective basis. Customer account balances are charged against the allowance when it is probable the receivable will not be recovered. Changes in the allowance during fiscal 2011, 2010 and 2009 were immaterial. There is no off-balance sheet credit exposure related to customer receivable balances.

Stock-based Compensation

Cabot recognizes stock-based awards granted to employees as compensation expense using a fair value method. Under the fair value recognition provisions, stock-based compensation cost is measured at the grant date based on the fair value of the award, and is recognized as expense over the service period, which generally represents the vesting period, and includes an estimate of the awards that will be forfeited, and an estimate of what level of performance the Company will achieve for Cabot's performance-based stock awards. Cabot calculates the fair value of its stock options using the Black-Scholes option pricing model. The fair value of restricted stock and restricted stock units is determined using the closing price of Cabot stock on the day of the grant.

Research and Technical Expenses

Research and technical expenses include salaries, equipment and material expenditures, and contractor fees and are expensed as incurred.

Income Taxes

Deferred income taxes are determined based on the estimated future tax effects of differences between financial statement carrying amounts and the tax bases of existing assets and liabilities. Deferred tax assets are recognized to the extent that realization of those assets is considered to be more likely than not.

A valuation allowance is established for deferred taxes when it is more likely than not that all or a portion of the deferred tax assets will not be realized. Provisions are made for the U.S. income tax liability and additional non-U.S. taxes on the undistributed earnings of non-U.S. subsidiaries, except for amounts Cabot has designated to be indefinitely reinvested.

Cabot records benefits for uncertain tax positions based on an assessment of whether the position is more likely than not to be sustained by the taxing authorities. If this threshold is not met, no tax benefit of the uncertain tax position is recognized. If the threshold is met, the tax benefit that is recognized is the largest amount that is greater than 50% likely of being realized upon ultimate settlement. This analysis presumes the taxing authorities' full knowledge of the positions taken and all relevant facts, but does not consider the time value of money. The Company also accrues for interest and penalties on its uncertain tax positions and includes such charges in its income tax provision in the Consolidated Statements of Operations.

Accumulated Other Comprehensive Income

Accumulated other comprehensive income, which is included as a component of stockholders' equity, includes unrealized gains or losses on available-for-sale marketable securities and derivative instruments, currency translation adjustments in foreign subsidiaries, translation adjustments on foreign equity securities and minimum pension liability adjustments.

Environmental Costs

Cabot accrues environmental costs when it is probable that a liability has been incurred and the amount can be reasonably estimated. When a single liability amount cannot be reasonably estimated, but a range can be reasonably estimated, Cabot accrues the amount that reflects the best estimate within that range or the low end of the range if no estimate within the range is better. The amount accrued reflects Cabot's assumptions about remediation requirements at the contaminated site, the nature of the remedy, the outcome of discussions with regulatory agencies and other potentially responsible parties at multi-party sites, and the number and financial viability of other potentially responsible parties. Cabot discounts certain of its long-term environmental liabilities to reflect the time value of money if the amount of the liability and the amount and timing of cash payments for the liability are fixed and reliably determinable. The liability will be discounted at a rate that will produce an amount at which the liability theoretically could be settled in an arm's length transaction with a third party. This discounted rate may not exceed the risk-free rate for maturities comparable to those of the liability. Cabot does not reduce its estimated liability for possible recoveries from insurance carriers. Proceeds from insurance carriers are recorded when realized by either the receipt of cash or a contractual agreement.

Use of Estimates

The preparation of consolidated financial statements in conformity with generally accepted accounting principles in the United States requires management to make certain estimates and assumptions that affect the reported amount of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reported period. Actual results could differ from those estimates.

Accounting Pronouncements

12 Months Ended

Sep. 30, 2011

Accounting Pronouncements

Accounting Pronouncements

Note B. Accounting Pronouncements

New and Adopted

On October 1, 2010 the Company adopted authoritative guidance on the consolidation of variable interest entities. The new guidance requires revised evaluations of whether entities represent variable interest entities, ongoing assessments of control over such entities, and additional disclosures for variable interests. The impact of the adoption is not material to the consolidated financial statements.

In September 2011, the FASB issued amended guidance on testing goodwill for impairment. Companies will now have the option to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If after considering the totality of events and circumstances an entity determines it is not more likely than not that the fair value of a reporting unit is less than its carrying amount, performing the two-step impairment is unnecessary. The amended guidance is effective for annual and interim goodwill impairment tests performed for fiscal years beginning after December 15, 2011 but early adoption is permitted. The Company will early adopt this amended guidance for its annual impairment test in fiscal 2012 and believes the impact will not be material to the consolidated financial statements.

Tabular disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 154
-Paragraph 2, 17, 18
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 28
-Paragraph 23, 24
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 01
-Paragraph b
-Subparagraph 6
-Article 10

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 1
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6801783&loc=d3e22580-107794

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Indirect Effects of a Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6515603

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Accounting Change
-URI http://asc.fasb.org/extlink&oid=6503790

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6507316

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Direct Effects of a Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6510796

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.10-01.(b)(6))
-URI http://asc.fasb.org/extlink&oid=6958853&loc=d3e46468-122699

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6801783&loc=d3e22583-107794

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Retrospective Application
-URI http://asc.fasb.org/extlink&oid=6523989

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-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=6372559&loc=d3e765-108305

Discontinued Operations

12 Months Ended

Sep. 30, 2011

Discontinued Operations

Discontinued Operations

Note C. Discontinued Operations

Cabot Supermetals Business

In August 2011, the Company entered into a Sale and Purchase Agreement (the "Purchase Agreement") with Global Advanced Metals Pty Ltd., an Australian company ("GAM"), for the sale of substantially all of the assets of the Company's Supermetals Business in exchange for a minimum of $401.5 million comprised of the following: (i) $175 million payable in cash at the closing, subject to certain working capital adjustments at closing, (ii) $175 million of 10.84% interest-bearing two-year promissory notes, which may be pre-paid by GAM at any time prior to maturity for an amount equal to $215 million (consisting of principal, interest and a prepayment premium), secured by liens on the property and assets of the acquired business and guaranteed by the GAM corporate group, (iii) quarterly contingent cash payments to be made in each calendar quarter that the promissory notes are outstanding in an amount equal to 50% of Adjusted EBITDA of the acquired business for the relevant calendar quarter, guaranteed to be at least $11.5 million for the first year following the closing of the transaction, and (iv) the assumption of certain liabilities associated with the Supermetals Business.

The parties expect the transaction to close by the end of calendar year 2011. Completion of the sale is subject to regulatory approval and certain other customary conditions. The Purchase Agreement is not subject to a financing condition.

In connection with the transaction, the parties have entered into a tantalum ore supply agreement under which the Company will sell to GAM all of the tantalum ore mined at the Company's mine in Manitoba, Canada for a period of three years following the closing of the transaction. The Company also entered into a transition services agreement for the Company to provide certain information technology applications and infrastructure and various administrative services to GAM during the transition period of six months from the closing date in exchange for one time and monthly service fees. GAM has the option to terminate such transition services with notice at any time and may elect to extend such services for up to three months. The future continuing cash flows from the disposed business to Cabot resulting from the tantalum ore supply agreement and transition services agreement are not significant and do not constitute a material continuing financial interest in the Supermetals Business.

The Supermetals Business, which had previously been presented as a separate reporting business, meets the criteria for being reported as a discontinued operation and has been segregated from continuing operations. The following table summarizes the results from discontinued operations:


	Years Ended September 30
	2011			2010			2009
	(Dollars in millions)
Net sales and other operating revenues	$	201		$	177		$	135

Income (loss) from operations before income taxes		84			42			(3	)
(Provision) benefit for income taxes		(31	)		(16	)		1

Income (loss) from discontinued operations, net of tax	$	53		$	26		$	(2	)

The following table summarizes the assets held for sale and the liabilities held for sale in the Company's Consolidated Balance Sheets:


	September 30,
	2011		2010
	(Dollars in millions)
Assets
Accounts and notes receivable, net of reserve for doubtful accounts	$	41	$	36
Inventories		64		66
Prepaid expenses and other current assets		1		1

Total current assets held for sale	$	106	$	103

Net property, plant and equipment	$	39	$	38
Other assets		—		2

Total noncurrent assets held for sale	$	39	$	40

Liabilities
Accounts payable and accrued liabilities	$	12	$	16

Total current liabilities held for sale	$	12	$	16

Other liabilities	$	6	$	6

Total noncurrent liabilities held for sale	$	6	$	6

Discontinued Operations – Other

In addition to the divesture of its Supermetals Business, the Company also has classified certain settlements associated with separate businesses divested ten or more years ago as part of Income (loss) from discontinued operations, net of tax in its Consolidated Statements of Operations for the fiscal years ended September 30, 2011 and 2009. These settlements resulted in net charges of less than $1 million in each of these years. No such charges were recorded in fiscal 2010.

The entire disclosure for the facts and circumstances leading to the completed or expected disposal, manner and timing of disposal, the gain (loss) recognized in the income statement and the income statement caption that includes that gain (loss), amounts of revenues and pretax profit or loss reported in discontinued operations, the segment in which the disposal group was reported, and the classification (whether sold or classified as held for sale) and carrying value of the assets and liabilities comprising the disposal group. Includes all disposal groups, including those classified as components of the entity (discontinued operations).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 144
-Paragraph 43-48
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2941-110230

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1510-107760

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1020-107759

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1012-107759

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e957-107759

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1474-107760

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6390789&loc=d3e2443-110228

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760

Inventories

12 Months Ended

Sep. 30, 2011

Inventories

Inventories

Note D. Inventories

Inventories, net of LIFO reserves, are as follows:


	September 30
	2011		2010
	(Dollars in millions)
Raw materials	$	120	$	94
Work in process		3		3
Finished goods		233		179
Other		37		31

Total	$	393	$	307

Inventories valued under the LIFO method comprised approximately 8% and 10% of total inventories at September 30, 2011 and 2010, respectively. At September 30, 2011 and 2010, the LIFO reserve was $53 million and $35 million, respectively. Other inventory is comprised of certain spare parts and supplies.

During fiscal 2009, inventory quantities were reduced at the Company's U.S. Rubber Blacks and Performance Products sites. These reductions led to liquidations of LIFO inventory quantities and resulted in a decrease of cost of goods sold of $5 million and an increase in net income of $3 million ($0.06 per diluted common share) for fiscal 2009. No such reductions occurred in either fiscal 2011 or fiscal 2010.

Cabot reviews inventory for both potential obsolescence and potential loss of value periodically. In this review, Cabot makes assumptions about the future demand for and market value of the inventory and, based on these assumptions, estimates the amount of obsolete, unmarketable or slow moving inventory. The inventory reserves were $10 million as of both September 30, 2011 and 2010.

Investments

12 Months Ended

Sep. 30, 2011

Investments

Investments

Note E. Investments

Equity Affiliates—Cabot has investments in equity affiliates in the Rubber Blacks, Performance Products and Fumed Metal Oxides Businesses. These investments are accounted for using the equity method. Cabot does not disclose its equity affiliate financial statements separately by entity because none of them are individually material to the consolidated financial statements. The following table presents summarized whole business income statement and balance sheet information for all of Cabot's equity method investments.


	September 30
	2011		2010		2009
	(Dollars in millions)
Condensed Income Statement Information:
Net sales	$	312	$	363	$	172
Gross profit		55		50		33
Net income		18		20		10
Condensed Balance Sheet Information:
Current assets	$	109	$	141	$	87
Non-current assets		55		73		64
Current liabilities		38		32		34
Non-current liabilities		3		50		7
Net assets		123		132		110

At September 30, 2011 and 2010, Cabot had equity affiliate investments of $60 million and $61 million, respectively. Dividends declared from these investments were $5 million, $6 million and $1 million in fiscal 2011, 2010 and 2009, respectively.

The entire disclosure for equity investment, or group of investments, for which combined disclosure is appropriate, including: (a) the name of each investee and percentage of ownership of common stock, (b) accounting policies for investments in common stock, (c) difference between the amount at which the investment is carried and the amount of underlying equity in net assets and the accounting treatment of the difference, (d) the total fair value of each identified investment for which a market value is available, (e) summarized information as to assets, liabilities, and results of operations of the investees (for investments in unconsolidated subsidiaries, common stock of joint ventures, or other investments using the equity method), and (f) material effects of possible conversions, exercises, or contingent issuances of the investee. Other disclosures include (a) the names of any investee in which the investor owns 20 percent or more of the voting stock and investment is not accounted for using the equity method, and the reasons why not, and (b) the names of any investee in which the investor owns less than 20 percent of the voting stock and the investment is accounted for using the equity method, and the reasons why it is.

Property, Plant And Equipment

Property, Plant And Equipment

12 Months Ended

Sep. 30, 2011

Property, Plant And Equipment

Note F. Property, Plant and Equipment

Property, plant and equipment is summarized as follows:


	September 30
	2011			2010
	(Dollars in millions)
Land and land improvements	$	73		$	69
Buildings		479			475
Machinery and equipment		2,076			2,011
Other		162			221
Construction in progress		177			102

Total property, plant and equipment		2,967			2,878
Less: accumulated depreciation		(1,931	)		(1,941	)

Net property, plant and equipment	$	1,036		$	937

Depreciation expense was $138 million, $137 million and $164 million for fiscal 2011, 2010 and 2009, respectively.

The entire disclosure for long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software. This disclosure may include property plant and equipment accounting policies and methodology, a schedule of property, plant and equipment gross, additions, deletions, transfers and other changes, depreciation, depletion and amortization expense, net, accumulated depreciation, depletion and amortization expense and useful lives, income statement disclosures, assets held for sale and public utility disclosures.

Goodwill And Other Intangible Assets

Goodwill And Other Intangible Assets

12 Months Ended

Sep. 30, 2011

Goodwill And Other Intangible Assets

Note G. Goodwill and Other Intangible Assets

Cabot had goodwill balances of $40 million and $39 million at September 30, 2011 and 2010, respectively. The carrying amount of goodwill attributable to each reporting unit with goodwill balances and the changes in those balances during the years ended September 30, 2011 and 2010 are as follows:


	Rubber Blacks		Fumed Metal Oxides		Security Materials		Total
	(Dollars in millions)
Balance at September 30, 2009	$	26	$	11	$	—	$	37
Goodwill acquired⁽¹⁾		—		—		1		1
Foreign currency translation adjustment		1		—		—		1

Balance at September 30, 2010		27		11		1		39
Foreign currency translation adjustment and other		—		—		1		1

Balance at September 30, 2011	$	27	$	11	$	2	$	40

⁽¹⁾	Goodwill acquired relates to the acquisition of Oxonica Materials Inc. in Security Materials.

Impairment tests are performed at least annually. The Company performed its annual impairment assessment as of March 31 of each year and determined that there were no impairments for any of the years presented.

Cabot does not have any indefinite-lived intangible assets. Finite-lived intangible assets which are included in Other assets in the Consolidated Balance Sheets consist of the following:


	Years Ended September 30
	2011							2010
	Gross Carrying Value		Accumulated Amortization			Net Intangible Assets		Gross Carrying Value		Accumulated Amortization			Net Intangible Assets
	(Dollars in millions)
Patents	$	2	$	(2	)	$	—	$	2	$	(2	)	$	—
Other intangible assets assets⁽¹⁾		3		—			3		3		—			3

Total intangible assets	$	5	$	(2	)	$	3	$	5	$	(2	)	$	3

⁽¹⁾	Other intangible assets relates to the acquisition of Oxonica Materials Inc. in Security Materials in fiscal 2010.

Intangible assets are amortized over their estimated useful lives, which range from six to fourteen years, with a weighted average amortization period of twelve years. Amortization expense amounted to less than $1 million in each of fiscal 2011, 2010 and 2009 and is included in cost of goods sold in the Consolidated Statements of Operations. Amortization expense is estimated to be less than $1 million in each of the next five fiscal years.

In July 2010, Cabot acquired 100% of the outstanding equity of Oxonica Materials Inc. ("OMI") from Oxonica Plc for total consideration of $5 million. OMI, now named Cabot Security Materials Inc., is developing surface enhanced raman scattering materials and detection methods, which are expected to expand Cabot's portfolio of security technologies.

The entire disclosure for the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain (loss) on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss.

Accounts Payable, Accrued Liabilities And Other Liabilities

Accounts Payable, Accrued Liabilities And Other Liabilities

12 Months Ended

Sep. 30, 2011

Accounts Payable, Accrued Liabilities And Other Liabilities

Note H. Accounts Payable, Accrued Liabilities and Other Liabilities

Accounts payable and accrued liabilities included in current liabilities consist of the following:


	September 30
	2011		2010
	(Dollars in millions)
Accounts payable	$	330	$	292
Accrued employee compensation		44		58
Accrued severance and restructuring		11		21
Other accrued liabilities		76		60

Total	$	461	$	431

Other long-term liabilities consist of the following:


	September 30
	2011		2010
	(Dollars in millions)
Employee benefit plan liabilities	$	161	$	160
Non-current tax liabilities		50		63
Financial instrument liabilities		39		39
Other accrued liabilities		49		56

Total	$	299	$	318

Debt And Other Obligations

12 Months Ended

Sep. 30, 2011

Debt And Other Obligations

Debt And Other Obligations

Note I. Debt and Other Obligations

The Company's long-term obligations, the calendar year in which they mature and their respective interest rates are summarized below:


	September 30
	2011			2010
	(Dollars in millions)
Variable Rate Debt:
$550 million Revolving Credit Facility, expires 2016	$	—		$	—
Chinese Renminbi Notes, due through 2012, 5.40%		15			16

Total variable rate debt		15			16
Fixed Rate Debt:
5% Notes due 2016	$	300		$	300
Medium Term Notes:
Notes due 2011, 7.26%	$	—		$	15
Notes due 2012, 7.70%—8.28%		30			30
Note due 2018, 7.42%		30			30
Notes due 2022, 8.346%—8.47%		15			15
Note due 2027, 6.57%—7.28%		8			8

Total Medium Term Notes		83			98
Eurobond, due 2013, 5.25%		178			179
ESOP Note, due 2013, 8.29%		14			20
Chinese Renminbi Notes, due 2012, 6.10%		5			4
Other, due 2027, 2%		5			5

Total fixed rate debt		585			606
Capital lease obligations, due through 2031		15			3
Unamortized debt discount		(2	)		(2	)

Total debt		613			623
Less current portion of long-term debt		(57	)		(23	)

Total long-term debt	$	556		$	600

$550 million Revolving Credit Facility—In August 2011, Cabot entered into a new committed unsecured revolving credit agreement. The credit agreement provides for a $550 million revolving credit facility through August 2016 and replaced the Company's previous $450 million revolving credit facility which was scheduled to expire in June 2014. The credit agreement contains an option, subject to the lenders' approval, to increase the facility to $750 million. All borrowings under the credit agreement will be based on variable interest rates. Generally, the interest rates are based upon LIBOR plus a spread. This spread, which was 1.125% as of September 30, 2011, is based on the Company's credit rating. Amounts committed under the credit agreement can also be utilized to provide letters of credit in certain circumstances. Previously issued letters of credit in the aggregate amount of approximately $29 million are treated as issued under the credit agreement as of September 30, 2011. The Company plans to use the credit agreement for general corporate purposes, which may include working capital, refinancing existing indebtedness, capital expenditures, share repurchases, and acquisitions. The credit agreement contains affirmative, negative and financial covenants and events of default customary for financings of this type. The financial covenants in the credit agreement include interest coverage, debt-to-EBITDA and subsidiary debt to total capitalization ratios. As of September 30, 2011, there were no outstanding drawn borrowings against this facility.

Chinese Renminbi Debt—The Company's consolidated Chinese subsidiaries had $20 million of unsecured long-term debt outstanding at both September 30, 2011 and 2010.

5% Notes due 2016—In fiscal 2009, Cabot issued $300 million in public notes with a coupon of 5% that will mature on October 1, 2016. These notes are unsecured and pay interest on April 1 and October 1 of each year. The net proceeds of this offering were $296 million after deducting discounts and issuance costs. The discount of approximately $2 million was recorded at issuance and is being amortized over the life of the notes. A portion of the proceeds was used to repay the outstanding indebtedness under the Company's revolving credit facility in fiscal 2009.

Medium Term Notes—At September 30, 2011 and 2010, there were $83 million and $98 million, respectively, of unsecured medium term notes outstanding issued to numerous lenders with various fixed interest rates and maturity dates. The weighted average maturity of the total outstanding medium term notes is 6.5 years with a weighted average interest rate of 7.9%. Certain of the medium term notes are designated as fair value hedges and accordingly are recorded at fair value. As described in Note L, the Company has entered into variable interest rate swaps for certain designated medium term notes to offset the changes in the fair value of the underlying debt.

Eurobond—A European subsidiary issued an unsecured $175 million U.S. dollar denominated bond with a fixed coupon rate of 5.25% in fiscal 2003. The functional currency of this subsidiary is the euro. The bond matures on September 1, 2013, with interest due on March 1 and September 1 of each year. A discount of approximately $1 million was recorded at issuance and is being amortized over the life of the bond. A portion of the eurobond is designated as a fair value hedge and accordingly is recorded at fair value. As described in Note L, the Company has entered into cross-currency swaps and a variable interest rate swap to hedge the variability in cash flows for changes in the exchange rates and to offset a portion of the changes in the fair value of the underlying debt.

ESOP Debt—In November 1988, Cabot's Employee Stock Ownership Plan ("ESOP") borrowed $75 million from an institutional lender in order to finance its purchase of Cabot shares. This debt bears interest at 8.29% per annum and is to be repaid in quarterly installments through December 31, 2013. Cabot, as guarantor, has reflected the outstanding balance of $14 million and $20 million as long-term debt in the Consolidated Balance Sheets at September 30, 2011 and 2010, respectively. An equal amount, representing deferred employee benefits, has been recorded as a reduction to stockholders' equity. Cabot contributed $4 million to the ESOP to service the debt during fiscal 2011, and $4 million for each of fiscal 2010 and 2009. Dividends on ESOP shares used for debt service were $2 million during fiscal 2011 and $3 million during each of fiscal 2010 and 2009. In addition, interest incurred on the ESOP debt was $1 million, $2 million, and $2 million during fiscal 2011, 2010 and 2009, respectively.

Capital Lease Obligations—Cabot had capital lease obligations for certain equipment and buildings with a present value of $15 million and $3 million at September 30, 2011 and 2010, respectively. Cabot will make payments totaling $29 million over the next 20 years, including $14 million of imputed interest. At September 30, 2011 and 2010, the original cost of capital lease assets was $24 million and $11 million, respectively, and the associated accumulated depreciation of assets under capital leases was $10 million and $8 million at September 30, 2011 and 2010, respectively. The amortization related to those assets under capital lease is included in depreciation expense.

Future Years Payment Schedule

The aggregate principal amounts of long-term debt and capital lease obligations due in each of the five years from fiscal 2012 through 2016 are as follows:


Fiscal Years Ended	Principal payments on long term debt⁽¹⁾		Payments on Capital Lease Obligations		Total
	(Dollars in millions)
2012	$	56	$	1	$	57
2013		182		1		183
2014		2		1		3
2015		—		1		1
2016		300		1		301
Thereafter		57		10		67

Total	$	597	$	15	$	612

⁽¹⁾	Payment of long-term debt excludes settlements of cross currency swaps.

Standby letters of credit—At September 30, 2011, the Company had provided standby letters of credit that were outstanding and not drawn totaling $37 million, which expire through fiscal 2012. The $37 million includes $29 million treated as issued under the credit agreement discussed previously and an additional $8 million of other standby letters of credit.

Short-term Notes Payable to Banks—The Company had unsecured short-term notes payable to banks of $86 million and $29 million as of September 30, 2011 and 2010, respectively, with a maturities of less than one year. The weighted-average interest rate on short-term notes payable was 5.3% and 4.6% for fiscal 2011 and 2010, respectively.

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

Fair Value Measurements

12 Months Ended

Sep. 30, 2011

Fair Value Measurements

Fair Value Measurements

Note J. Fair Value Measurements

The FASB authoritative guidance on fair value measurements defines fair value, establishes a framework for measuring fair value in generally accepted accounting principles, and expands disclosures about fair value measurements. The disclosures focus on the inputs used to measure fair value. The guidance establishes the following hierarchy for categorizing these inputs:

There were no transfers between level 1 and level 2, or transfers into or out of level 3, during fiscal 2011 or 2010.

The following table presents information about the Company's financial assets and liabilities measured at fair value on a recurring basis as of September 30, 2011 and 2010. The derivatives presented in the table below are presented by derivative type, net of the legal right to offset derivative settlements by each counterparty:


	September 30
	2011		2010
	Level 2 Inputs		Level 2 Inputs
	(Dollars in Millions)
Assets at fair value:
Guaranteed investment contract⁽¹⁾	$	14	$	14
Derivatives relating to interest rates⁽²⁾		3		5

Total assets at fair value	$	17	$	19

Liabilities at fair value:
Derivatives relating to foreign currency⁽²⁾	$	41	$	42
Hedged long-term debt		61		77

Total liabilities at fair value	$	102	$	119

⁽¹⁾	Included in "Other assets" in the Consolidated Balance Sheets.

⁽²⁾	Included in "Prepaid expenses and other current assets", "Other assets", "Accounts payable and accrued liabilities" and "Other liabilities" in the Consolidated Balance Sheets.

During fiscal 2010, Cabot's management concluded that the carrying value of land related to a former carbon black facility exceeded its fair value of $6 million based on a comparison of similar facilities in the region. Accordingly, the Company recorded an impairment charge of $2 million within Cost of sales in the Consolidated Statement of Operations to write this land down to its fair value. During fiscal 2011, there was an additional impairment charge of less than $1 million on the same land. The fair value of the land, which remains at $6 million, is included in Other assets in the Consolidated Balance Sheets.

Tabular disclosure of the fair value measurement of assets and liabilities which includes [financial] instruments measured at fair value that are classified in stockholders' equity. Such assets and liabilities may be measured on a recurring or nonrecurring basis. The disclosures which may be required or desired include: (1) for assets and liabilities measured on a recurring basis, disclosure may include: (a) the fair value measurements at the reporting date; (b) the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets or liabilities (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3); (c) for fair value measurements using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (i) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (ii) purchases, sales, issuances, and settlements (net); (iii) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs); (d) the amount of the total gains or losses for the period in subparagraph (c) (i) above included in earnings (or changes in net assets) that are attributable to the change in unrealized gains or losses relating to those assets and liabilities still held at the reporting date and a description of where those unrealized gains or losses are reported in the statement of income (or activities); (e) the valuation technique(s) used to measure fair value and a discussion of changes in valuation techniques, if any, during the period and (2) for assets and liabilities that are measured at fair value on a nonrecurring basis (for example, impaired assets) disclosure may include, in addition to (a) above: (a) the reasons for the fair value measurements recorded; (b) the same as (b) above; (c) for fair value measurements using significant unobservable inputs (Level 3), a description of the inputs and the information used to develop the inputs; and (d) the valuation technique(s) used to measure fair value and a discussion of changes, if any, in the valuation technique(s) used to measure similar assets and/or liabilities in prior periods. Where the quoted price in an active market for the identical liability is not available, the Level 1 input is the quoted price of an identical liability when traded as an asset.

Fair Value Of Financial Instruments

Fair Value Of Financial Instruments

12 Months Ended

Sep. 30, 2011

Fair Value Of Financial Instruments

Note K. Fair Value of Financial Instruments

The carrying amounts and fair values of the Company's financial instruments at September 30, 2011 and 2010 are as follows:


	2011				2010
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
	(Dollars in millions)
Assets:
Cash and cash equivalents	$	286	$	286	$	387	$	387
Accounts and notes receivable		659		659		540		540
Derivative instruments		1		1		2		2
Liabilities:
Notes payable to banks		86		86		29		29
Accounts payable and accrued liabilities		461		461		431		431
Long-term debt—fixed rate		585		633		604		661
Long-term debt—floating rate		15		15		16		16
Capital lease obligations		15		15		3		3
Derivative instruments		39		39		39		39

At September 30, 2011 and 2010, the fair values of cash and cash equivalents, accounts and notes receivable, accounts payable and accrued liabilities, and notes payable to banks approximated carrying values due to the short-term nature of these instruments. The estimated fair values of derivative instruments are valued as described in Note J. The fair value of Cabot's fixed rate long-term debt and capital lease obligations are estimated based on comparable quoted market prices where available, or estimated using current interest rates at the respective period ends. The carrying amounts of Cabot's floating rate long-term debt approximate their fair value.

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Financial Instruments

12 Months Ended

Sep. 30, 2011

Financial Instruments

Financial Instruments

Note L. Financial Instruments

Risk Management

Cabot's business operations are exposed to changes in interest rates, foreign currency exchange rates and commodity prices because Cabot finances certain operations through long and short-term borrowings, denominates transactions in a variety of foreign currencies and purchases certain commoditized raw materials. Changes in these rates and prices may have an impact on future cash flows and earnings. The Company manages these risks through normal operating and financing activities and, when deemed appropriate, through the use of derivative financial instruments.

The Company has policies governing the use of derivative instruments and does not enter into financial instruments for trading or speculative purposes.

By using derivative instruments, Cabot is subject to credit and market risk. If a counterparty fails to fulfill its performance obligations under a derivative contract, Cabot's credit risk will equal the fair value of the derivative. Generally, when the fair value of a derivative contract is positive, the counterparty owes Cabot, thus creating a payment risk for Cabot. The Company minimizes counterparty credit (or repayment) risk by entering into transactions with major financial institutions of investment grade credit rating. As of September 30, 2011, the counterparties with which the Company has executed derivatives carried a Standard and Poor's credit rating between A- and AA-, inclusive. Cabot's exposure to market risk is not hedged in a manner that completely eliminates the effects of changing market conditions on earnings or cash flow. No significant concentration of credit risk existed at September 30, 2011.

Interest Rate Risk Management

Cabot's objective is to maintain a certain fixed-to-floating interest rate mix on the Company's debt portfolio. Cabot enters into interest rate swaps as a hedge of the underlying debt instruments to effectively change the characteristics of the interest rate without changing the debt instrument. The following table provides details of the derivatives held as of September 30, 2011 and 2010 to manage interest rate risk.


		Notional Amount
Description	Borrowing	September 30, 2011	September 30, 2010	Hedge Designation
Interest Rate Swap—Fixed to Variable	Eurobond (20% of $175 million)	USD 35 million	USD 35 million	Fair Value
Interest Rate Swap—Fixed to Variable⁽¹⁾	Medium Term Notes	—	USD 15 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 8 million	USD 8 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 5 million	USD 5 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 5 million	USD 5 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 5 million	USD 5 million	Fair Value

⁽¹⁾	Cabot's interest rate swap derivative instrument and the hedged debt borrowing matured during fiscal 2011.

Foreign Currency Risk Management

Cabot's international operations are subject to certain risks, including currency exchange rate fluctuations and government actions. Cabot endeavors to match the currency in which debt is issued to the currency of the Company's major, stable cash receipts. In some situations Cabot has issued debt denominated in U.S. dollars and then entered into cross currency swaps that exchange the dollar principal and interest payments into a currency where the Company expects long-term, stable cash receipts.

Additionally, the Company has foreign currency exposure arising from its net investments in foreign operations. Cabot, from time to time, enters into cross-currency swaps to mitigate the impact of currency rate changes on the Company's net investments.

The Company also has foreign currency exposure arising from the denomination of assets and liabilities in foreign currencies other than the functional currency of a given subsidiary as well as the risk that currency fluctuations could affect the dollar value of future cash flows generated in foreign currencies. Accordingly, Cabot uses short-term forward contracts to minimize the exposure to foreign currency risk. These forward contracts typically have a duration of 30 days.

In certain situations where the Company has forecasted purchases under a long-term commitment or forecasted sales denominated in a foreign currency, Cabot may enter into appropriate financial instruments in accordance with the Company's risk management policy to hedge future cash flow exposures. The following table provides details of the derivatives held as of September 30, 2011 and 2010 to manage foreign currency risk.


Description	Borrowing	Notional Amount		Hedge Designation
Description	Borrowing	September 30, 2011	September 30, 2010	Hedge Designation
Cross Currency Swap	Eurobond (80% of $175 million)	USD 140 million swapped to EUR 124 million	USD 140 million swapped to EUR 124 million	No designation

Cross Currency Swap	Eurobond (20% of $175 million)	USD 35 million swapped to EUR 31 million	USD 35 million swapped to EUR 31 million	No designation

Forward Foreign Currency Contracts ⁽¹⁾	N/A	USD 54 million	USD 23 million	No designation

Forward Foreign Currency Contracts ⁽²⁾	N/A	JPY 12 million	—	Cash Flow

⁽¹⁾	Cabot's forward foreign exchange contracts are denominated primarily in the Australian dollar, British pound sterling, Canadian dollar, Euro, and Japanese yen.

⁽²⁾	Cabot's forward foreign exchange contracts designated as cash flow hedges were entered into during fiscal 2011.

Commodity Risk Management

Certain of Cabot's carbon black plants in Europe are subject to mandatory greenhouse gas emission trading schemes. Cabot's objective is to ensure compliance with the European Union Emission Trading Scheme, which is based upon a Cap-and-Trade system that establishes a maximum allowable emission credit for each ton of CO₂ emitted. European Union Allowances ("EUA") originate from the individual EU member state's country allocation process and are issued by that country's government. A company that has an excess of EUAs based on the CO₂ emissions limits may sell EUAs in the Emission Trading Scheme and if they have a shortfall, a company can buy EUAs or Certified Emission Reduction ("CER") units to comply.

In order to limit variability in cost to Cabot's European operations, the Company purchased CERs and sold EUAs, which settle each December until 2012. The following table provides details of the derivatives held as of September 30, 2011 and 2010 to manage commodity risk.


		Notional Amount
Description	Net Buyer / Net Seller	September 30, 2011	September 30, 2010	Hedge Designation
CERs	Buyer	EUR 1 million	EUR 2 million	No designation
EUAs	Seller	EUR 1 million	EUR 2 million	No designation

Accounting for Derivative Instruments and Hedging Activities

The Company determines the fair value of financial instruments using quoted market prices whenever available. When quoted market prices are not available for various types of financial instruments (such as forwards, options and swaps), the Company uses standard models with market-based inputs, which take into account the present value of estimated future cash flows and the ability of the financial counterparty to perform.

Fair Value Hedge

For interest rate swaps designated as fair value hedges, the Company uses standard models with market-based inputs. The significant inputs to these models are interest rate curves for discounting future cash flows. For derivative instruments that are designated and qualify as fair value hedges, the gain or loss on the derivative as well as the offsetting gain or loss on the hedged item attributable to the hedged risk are recognized in current period earnings.

Cash Flow Hedge

For cross currency swaps and foreign currency forward contracts designated as cash flow hedges, the Company uses standard models with market-based inputs. The significant inputs to these models are interest rate curves for discounting future cash flows, and exchange rate curves of the foreign currency for translating future cash flows. For derivative instruments that are designated and qualify as cash flow hedges, the effective portion of the gain or loss on the derivative is recorded in Accumulated other comprehensive income and reclassified to earnings in the same period or periods during which the hedged transaction affects earnings. Gains and losses on the derivative representing either hedge ineffectiveness or hedge components excluded from the assessment of effectiveness are recognized in current period earnings.

Net Investment Hedge

For cross currency swaps designated as net investment hedges, the Company uses standard models with market-based inputs. The significant inputs to these models are interest rate curves for discounting future cash flows. For net investment hedges, changes in the fair value of the effective portion of the derivatives' gains or losses are reported as foreign currency translation gains or losses in Accumulated other comprehensive income while changes in the ineffective portion are reported in earnings. The gains or losses on derivative instruments reported in Accumulated other comprehensive income are reclassified to earnings in the period in which earnings are affected by the underlying item, such as a disposal or substantial liquidation of the entities being hedged.

As of September 30, 2011, there were no open derivatives designated as net investment hedges. During the first quarter of fiscal 2010, the Company's derivative instrument, which swapped $20 million to JPY 2.5 billion, matured leading to a cash settlement payment of $7 million in that period. The cumulative loss related to this net investment hedge recorded in Accumulated other comprehensive income as of both September 30, 2011 and 2010 was $27 million.

Other Derivative Instruments

From time to time, the Company may enter into certain derivative instruments that may not be designated as hedges for accounting purposes, which include cross currency swaps, foreign currency forward contracts and commodity derivatives. For cross currency swaps and foreign currency forward contracts not designated as hedges, the Company uses standard models with market-based inputs. The significant inputs to these models are interest rate curves for discounting future cash flows, and exchange rate curves of the foreign currency for translating future cash flows. In determining the fair value of the commodity derivatives, the significant inputs to valuation models are quoted market prices of similar instruments in active markets. Although these derivatives do not qualify for hedge accounting, Cabot believes that such instruments are closely correlated with the underlying exposure, thus managing the associated risk. The gains or losses from changes in the fair value of derivative instruments that are not accounted for as hedges are recognized in current period earnings.

Derivative Activity and Balance Classification

On January 1, 2009, Cabot adopted the authoritative guidance issued by the FASB on disclosures about derivative instruments and hedging activities. Disclosure regarding the impact on earnings of amounts reclassified from other comprehensive income, as required by this guidance, has not been included for fiscal 2009 as it was not material and the guidance was effective only for the last three quarters of fiscal 2009.

During fiscal 2011, for derivatives designated as hedges, the change in unrealized gains in Accumulated other comprehensive income, the hedge ineffectiveness recognized in earnings, the realized gains or losses reclassified from Accumulated other comprehensive income, and the losses reclassified from Accumulated other comprehensive income to earnings were immaterial. During fiscal 2011, a loss of $2 million was recognized in earnings as a result of the remeasurement to Euros of the $175 million bond held by one of Cabot's European subsidiaries. This loss, which was recognized in earnings through Other expense within the Consolidated Statement of Operations, was offset by a gain of $1 million from Cabot's cross currency swaps that are not designated as hedges, but which Cabot entered into to offset the foreign currency translation exposure on the debt. Additionally, during fiscal 2011, Cabot recognized in earnings through Other expense within the Consolidated Statement of Operations, gains of $3 million related to its foreign currency forward contracts, which were not designated as hedges.

During fiscal 2010, for derivatives designated as hedges, the change in unrealized gains in Accumulated other comprehensive income and the hedge ineffectiveness recognized in earnings was immaterial. Additionally, during this period, there were no gains or losses reclassified from Accumulated other comprehensive income to earnings. During fiscal 2010, a loss of $14 million was recognized in earnings as a result of the remeasurement to Euros of the $175 million bond held by one of Cabot's European subsidiaries. This loss, which was recognized in earnings through Other expense within the Consolidated Statement of Operations, was offset by a gain of $16 million from Cabot's cross currency swaps that are not designated as hedges, but which Cabot entered into to offset the foreign currency translation exposure on the debt. Additionally, during fiscal 2010, Cabot recognized in earnings through Other expense within the Consolidated Statement of Operations, gains of $7 million related to its foreign currency forward contracts, which were not designated as hedges.

The following table provides the fair value and Consolidated Balance Sheets presentations of derivative instruments by each derivative type, without regard to the legal right to offset derivative settlement by each counterparty:


Fair Value of Derivative Instruments	Consolidated Balance Sheet Caption	September 30, 2011		September 30, 2010
		(Dollars in millions)
Asset Derivatives
Derivatives designated as hedges Interest rate⁽¹⁾	Prepaid expenses and other current assets and Other liabilities	$	3	$	5

Total derivatives designated as hedges		$	3	$	5

Derivatives not designated as hedges Foreign currency	Prepaid expenses and other current assets	$	1	$	—
Commodity contracts⁽²⁾	Prepaid expenses and other current assets, and Other assets		1		2

Total derivatives not designated as hedges		$	2	$	2

Total Asset Derivatives		$	5	$	7

Liability Derivatives
Derivatives designated as hedges Foreign currency	Accounts payable and accrued liabilities	$	1	$	—

Total derivatives designated as hedges		$	1	$	—

Derivatives not designated as hedges Foreign currency⁽¹⁾	Accounts payable and accrued liabilities, and Other liabilities	$	41	$	42
Commodity contracts⁽²⁾	Prepaid expenses and other current assets, and Other assets		1		2

Total derivatives not designated as hedges		$	42	$	44

Total Liability Derivatives		$	43	$	44

⁽¹⁾

Contracts of $3 million and $4 million presented on a gross basis in this table at September 30, 2011 and 2010, respectively, have the legal right to offset against other types of contracts with a common counterparty and, therefore, are presented on a net basis in noncurrent "Other liabilities" in the consolidated balance sheet.

⁽²⁾	Contracts in an asset and liability position presented on a gross basis in this table have the legal right of offset and, therefore, are presented on a net basis in "Prepaid expenses and other current assets" and noncurrent "Other assets" in the consolidated balance sheet.

See Note J "Fair Value Measurements" for classification of derivatives by input level. The net after-tax amounts to be reclassified from accumulated other comprehensive income to earnings within the next 12 months are expected to be immaterial.

Tabular disclosure of the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such certain disclosures about the financial instruments, assets, and liabilities include: (1) the fair value of the required items together with their carrying amounts (as appropriate) and (2) the methodology and assumptions used in developing such estimates of fair value.

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Venezuela

12 Months Ended

Sep. 30, 2011

Venezuela

Venezuela

Note M. Venezuela

Cabot owns 49% of an operating affiliate in Venezuela, which is accounted for as an equity affiliate, through wholly owned subsidiaries that carry the investment and receive its dividends. As of September 30, 2011, these subsidiaries carried the operating affiliate investment of $26 million and held 21 million bolivars ($5 million) in cash and dividends receivable. Historically, the operating affiliate pays dividends to Cabot's wholly owned subsidiaries either in bolivars or in U.S. dollars. Prior to 2009, dividends denominated in bolivars were received and then repatriated outside Venezuela in exchange for U.S. dollars. Over the past several years, however, there have been significant efforts on the part of the Venezuelan government to control the outflows of U.S. dollars from the country. These efforts include controls over when and if U.S. dollars can be repatriated and the enforcement of strict bolivar/U.S. dollar conversion rate standards, which effectively fix the exchange rate at 4.30B/$. Accordingly, the repatriation of dividends has become difficult.

Given the uncertainties around the convertibility of the Venezuelan bolivar to the U.S. dollar and the ability of entities to actually repatriate U.S. dollars from Venezuela, the Company has endeavored, whenever possible, to repatriate the Company's cash from its Venezuelan subsidiaries using available mechanisms. At the same time, management has closely monitored its investment in the operating affiliate in Venezuela to ensure that the investment continues to be recoverable. The Company has repatriated $1 million from Venezuela in fiscal 2011 and none in fiscal 2010.

In January 2010, the Venezuelan government announced a devaluation of the bolivar from 2.15B/$ to two official rates set by the Venezuelan Central Bank, an essentials rate at 2.60 B/$ and a non-essentials rate at 4.30 B/$. The latter rate is the rate that Cabot believes would continue to be available to the operating affiliate to transact its ordinary activities. In January 2011, the essentials exchange rate was increased from 2.60 B/$ to 4.30 B/$, making the essentials rate equal to the non-essentials rate.

Cabot determined, as of January 1, 2010, that the Venezuelan economy was highly inflationary. Accordingly, since the second quarter of fiscal 2010, Cabot has remeasured all transactions of the operating affiliate denominated in bolivars to U.S. dollars using the rate of 4.30 B/$. Because the exchange rate has remained stable for all the periods presented since the determination that the operating subsidiary was operating in an hyperinflationary environment, the amounts recorded in the income statement relative to translation gains or losses have amounted to less than $1 million in each of fiscal 2011 and 2010.

The Company still intends to convert substantially all bolivars held by its Venezuelan subsidiaries to U.S. dollars as soon as practical and continues to monitor for opportunities to convert its bolivars through Venezuelan government, or government backed, bond offerings.

While the events relating to official exchange rate movements did not have a material impact on Cabot's operating affiliate, the Company continues to monitor developments in Venezuela and their potential impact on it. Cabot uses a discounted cash flow model to determine if investments are impaired when triggering events such as changes in the business environment occur. Critical considerations of the model include the profitability of the operating affiliate and the ability to repatriate its earnings. Based on the profitability of the operating affiliate and uncertainty concerning the continuation of the current currency restrictions, as evidenced by the successful remittance of dividends in fiscal 2011, the Company does not believe that the investment in the operating affiliate is impaired.

Employee Benefit Plans

12 Months Ended

Sep. 30, 2011

Employee Benefit Plans

Employee Benefit Plans

Note N. Employee Benefit Plans

Cabot provides both defined benefit and defined contribution plans for its employees. The defined benefit plans consist of the Cabot Cash Balance Plan ("CBP"), a Supplemental Cash Balance Plan ("SCBP") and several foreign pension plans. The defined contribution plans consist of the Cabot Retirement Savings Plan ("RSP"), a Supplemental Retirement Savings Plan ("SRSP") and several foreign plans. Cabot also provides postretirement benefit plans, which include medical coverage and life insurance.

All information included in this footnote and the related tables include amounts pertaining to the Company's Supermetals Business, unless indicated otherwise.

Defined Contribution Plans

Cabot recognized expenses related to U.S. and foreign defined contribution plans of $7 million in fiscal year 2011 and $9 million in each of fiscal year 2010 and 2009.

Retirement Savings Plan

The RSP is a U.S. defined contribution plan, which encourages long-term systematic savings and provides funds for retirement or possible earlier needs. The RSP has two components, a 401(k) plan and an Employee Stock Ownership Plan ("ESOP").

401(k)

The 401(k) component of the plan allows an eligible participant to contribute a percentage of his or her eligible compensation on a before-tax or after-tax basis. For employees not subject to a collective bargaining agreement, Cabot makes a matching contribution of 75% of a participant's contribution of up to 7.5% of the participant's eligible compensation, making the maximum matching contribution an amount equal to 5.625% of a participant's eligible compensation. This matching contribution is in the form of Cabot common stock and is made on a quarterly basis.

Employee Stock Ownership Plan

Other than certain employees subject to collective bargaining agreements, all eligible employees of Cabot and its participating subsidiaries in the U.S. participate in the ESOP component of the plan. Under the ESOP, which is 100% Company funded, 108,696.645 shares of Cabot common stock are allocated to participants' accounts at the end of each quarter. These ESOP allocations will continue to be made quarterly until December 31, 2013, at which point all shares available for distribution under the ESOP will have been allocated to participant accounts. These shares are allocated based on a pre-determined formula. Cabot has established a minimum and maximum contribution percentage of total eligible pay of 4% and 8%, respectively. The actual contribution percentage in any given quarter varies depending on Cabot's stock price on the last day of the relevant quarter, the total eligible compensation and the amount of the dividends allocated to participants. If the calculated contribution allocation falls below 4%, the Company makes an additional contribution in the form of Cabot common stock to bring the total contribution to 4% for the participant. If the calculated contribution allocation exceeds 8% of eligible compensation, the excess shares are used to fund the Company match on the 401(k) contributions. If there are still shares remaining after the Company match has been allocated, the remaining shares are allocated to all participants in the ESOP as additional contribution shares. Compensation expense related to the ESOP was $4 million in each of fiscal year 2011, 2010 and 2009.

Supplemental Retirement Savings Plan

Cabot's SRSP provides benefits to highly compensated employees in circumstances in which the maximum limits established under the Employee Retirement Income Security Act of 1974 ("ERISA") and the Internal Revenue Code prevent them from receiving Company matching and ESOP contributions provided under the qualified RSP. The SRSP is non-qualified and unfunded. See Note O for further information on the SRSP.

Defined Benefit Plans

Defined benefit plans provide pre-determined benefits to employees that are distributed upon retirement. Measurement of defined benefit pension expense is based on assumptions used to value the defined benefit pension liability (including assets) at the beginning of the year. The CBP and certain foreign pension plans generally use the straight-line method of amortization over five years for the unrecognized net gains and losses. Cabot used a September 30 measurement date for all U.S. and foreign plan obligations and assets in both fiscal 2011 and 2010. Cabot is making all required contributions to the plans.

The accumulated benefit obligation was $140 million for the U.S. defined benefit plans and $218 million for the foreign plans as of September 30, 2011 and $138 million for the U.S. defined benefit plans and $224 million for the foreign plans as of September 30, 2010.

Cash Balance Plan

The CBP is a hybrid defined benefit pension plan in which participants in the CBP accrue benefits in the form of account balances, with a guaranteed rate of return and defined notional contributions. The notional contributions take the form of pay-based credits, which are computed as a percentage of eligible pay and credited quarterly to participant accounts. Interest is credited quarterly based on the average one-year Treasury bill rate for the month of November in the preceding calendar year. As of September 30, 2011, 54 employees have "grandfathered" benefits under a traditional defined benefit formula, which, under certain circumstances, may entitle them to benefits in addition to those accrued under the CBP formula described above. Cabot contributes to the plan based on the fair value of plan assets and associated returns and Cabot's obligations and their timing.

Supplemental Cash Balance Plan

Cabot's SCBP provides benefits to highly compensated employees in circumstances in which the maximum limits established under ERISA and the Internal Revenue Code prevent them from receiving some of the benefits provided under the qualified CBP. This plan is non-qualified and unfunded. The obligations in connection with the SCBP plan were $6 million and $4 million as of September 30, 2011 and 2010, respectively, and have been recorded in other liabilities. Both the CBP and the SCBP qualify as defined benefit plans.

Postretirement Benefit Plans

Cabot's postretirement benefit plans provide certain health care and life insurance benefits for retired employees. Typical of such plans, the Cabot postretirement benefit plans are unfunded. Cabot funds the plans as claims or insurance premiums come due. In order to limit its financial exposure, Cabot established a per retiree cap in the U.S. in 1992 on the amount it would contribute to retiree medical costs. Cabot made additional changes effective January 1, 2010 to its postretirement medical and life insurance plans that significantly reduce the number of current employees eligible to receive Company provided retiree life insurance and Company contributions towards retiree medical premiums in the future.

The following provides information about benefit obligations, plan assets, the funded status and weighted-average assumptions of the defined benefit pension and postretirement benefit plans:


	Years Ended September 30
	2011						2010						2011						2010
	Pension Benefits												Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign			U.S.			Foreign
	(Dollars in millions)
Change in Benefit Obligations:
Benefit obligation at beginning of year	$	143		$	241		$	137		$	228		$	69		$	15		$	69		$	15
Service cost		5			6			5			5			1			—			1			—
Interest cost		6			11			7			10			2			1			3			1
Plan participants' contribution		—			1			—			1			—			—			—			—
Foreign currency exchange rate changes		—			1			—			(2	)		—			—			—			—
Loss (gain) from changes in actuarial assumptions		2			(9	)		6			19			(1	)		(1	)		3			—
Benefits paid ⁽¹⁾		(9	)		(16	)		(12	)		(20	)		(5	)		—			(6	)		—
Plan amendments		—			—			—			—			(2	)		—			(1	)		—
Settlements or curtailment gain		—			(1	)		—			—			—			—			—			(1	)
Other		—			2			—			—			—			—			—			—

Benefit obligation at end of year	$	147		$	236		$	143		$	241		$	64		$	15		$	69		$	15


	Years Ended September 30
	2011						2010						2011						2010
	Pension Benefits												Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign			U.S.			Foreign
	(Dollars in millions)
Change in Plan Assets:
Fair value of plan assets at beginning of year	$	104		$	197		$	104		$	193		$	—		$	—		$	—		$	—
Actual return on plan assets		8			2			10			16			—			—			—			—
Employer contribution		—			13			2			9			5			—			6			—
Plan participants' contribution		—			1			—			1			—			—			—			—
Foreign currency exchange rate changes		—			—			—			(2	)		—			—			—			—
Benefits paid⁽¹⁾		(9	)		(16	)		(12	)		(20	)		(5	)		—			(6	)		—

Fair value of plan assets at end of year	$	103		$	197		$	104		$	197		$	—		$	—		$	—		$	—

Funded status	$	(44	)	$	(39	)	$	(39	)	$	(44	)	$	(64	)	$	(15	)	$	(69	)	$	(15	)

Recognized liability⁽²⁾	$	(44	)	$	(39	)	$	(39	)	$	(44	)	$	(64	)	$	(15	)	$	(69	)	$	(15	)

⁽¹⁾	Included in this amount is $2 million and $1 million that the Company paid directly to the participants in its defined benefit plans in fiscal 2011 and 2010, respectively.

⁽²⁾	Included in this amount is $4 million of net pension liability as of September 30, 2011 and 2010 related to the Supermetals Business presented as Noncurrent Liabilities Held For Sale in the Consolidated Balance Sheets.

Pension Assumptions and Strategy

The following assumptions were used to determine the pension benefit obligations at September 30:


	Assumptions as of September 30
	2011						2010						2009
	Pension Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign
Actuarial assumptions as of the year-end measurement date:
Discount rate		4.5	%		4.8	%		4.5	%		4.4	%		5.3	%		5.0	%
Rate of increase in compensation		3.8	%		3.1	%		3.8	%		3.3	%		3.8	%		3.4	%
Actuarial assumptions used to determine net periodic benefit cost during the year:
Discount rate		4.5	%		4.3	%		5.3	%		5.0	%		7.5	%		6.4	%
Expected long-term rate of return on plan assets		7.8	%		6.1	%		7.8	%		6.1	%		7.8	%		6.5	%
Rate of increase in compensation		3.8	%		3.3	%		3.8	%		3.4	%		4.5	%		3.8	%

Post Retirement Assumptions and Strategy

The following assumptions were used to determine the post retirement benefit obligations at September 30:


	Assumptions as of September 30
	2011						2010						2009
	Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign
Actuarial assumptions as of the year-end measurement date:
Discount rate		4.5	%		4.9	%		4.5	%		4.8	%		5.3	%		5.2	%
Initial health care cost trend rate		8.5	%		8.0	%		7.5	%		8.0	%		8.0	%		9.0	%
Actuarial assumptions used to determine net cost during the year:
Discount rate		4.5	%		4.8	%		5.3	%		5.2	%		7.5	%		7.1	%
Initial health care cost trend rate		7.5	%		8.0	%		8.0	%		9.0	%		8.0	%		9.0	%

Cabot uses discount rates as of September 30, the plans' measurement date, to determine future benefit obligations under its U.S. and foreign defined benefit plans. The discount rates for the defined benefit plans in the U.S., Canada, UAE, Euro-zone, Japan, Switzerland and the U.K. are derived from yield curves that reflect high quality corporate bond yield or swap rate information in each region and reflect the characteristics of Cabot's employee benefit plans. The discount rates for the defined benefit plans in Czech Republic and Indonesia are based on government bond indices that best reflect the durations of the plans, adjusted for credit spreads presented in selected AA corporate bond indices.

The rates utilized are selected because they represent long-term, high quality, fixed income benchmarks that approximate the long-term nature of Cabot's pension obligations and related payouts.


	Years Ended September 30
	2011						2010						2011						2010
	Pension Benefits												Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign			U.S.			Foreign
	(Dollars in millions)
Net Amounts Recognized in the Consolidated Balance Sheets
Noncurrent assets	$	—		$	10		$	—		$	5		$	—		$	—		$	—		$	—
Current liabilities		—			(1	)		(1	)		(1	)		(6	)		—			(6	)		—
Noncurrent liabilities		(44	)		(48	)		(38	)		(48	)		(58	)		(15	)		(63	)		(15	)

Amounts recognized in Accumulated other comprehensive income (loss) at September 30, 2011 and 2010 were as follows:


	Years Ended September 30
	2011				2010				2011					2010
	Pension Benefits								Postretirement Benefits
	U.S.		Foreign		U.S.		Foreign		U.S.			Foreign		U.S.			Foreign
	(Dollars in millions)
Net actuarial loss	$	34	$	52	$	32	$	54	$	2		$	2	$	3		$	3
Net prior service cost (credit)		1		—		1		—		(14	)		—		(16	)		—

Balance in accumulated other comprehensive income, pretax	$	35	$	52	$	33	$	54	$	(12	)	$	2	$	(13	)	$	3

In fiscal 2012, an estimated net loss of $4 million will be amortized from accumulated other comprehensive income to net periodic benefit cost. In addition, amortization of estimated prior service credits of $3 million for other postretirement benefits will be amortized from accumulated other comprehensive income to net periodic benefit costs in fiscal 2012.

Estimated Future Benefit Payments

The Company expects that the following benefit payments will be made to plan participants in the years from 2012 to 2021:


	Pension Benefits				Postretirement Benefits
	U.S.		Foreign		U.S.		Foreign
	(Dollars in millions)
Years Ended:
2012	$	11	$	12	$	6	$	1
2013		10		17		6		—
2014		11		13		6		—
2015		11		13		6		—
2016		11		15		5		1
2017-2021		65		83		25		5

The Company expects to contribute $8 million and $12 million related to its U.S. and foreign pension plans, respectively, in fiscal 2012.

Net periodic defined benefit pension and other postretirement benefit costs include the following components:


	Years Ended September 30
	2011						2010						2009						2011					2010					2009
	Pension Benefits																		Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign			U.S.			Foreign		U.S.			Foreign		U.S.			Foreign
	(Dollars in millions)
Service cost	$	5		$	6		$	5		$	5		$	4		$	5			1		$	—	$	1		$	—	$	2		$	—
Interest cost		6			11			7			11			8			12			2			1		3			1		5			1
Expected return on plan assets		(8	)		(13	)		(9	)		(11	)		(9	)		(12	)		—			—		—			—		—			—
Amortization of prior service cost (credit)		—			—			—			—			—			—			(3	)		—		(4	)		—		(1	)		—
Net losses (gains)		—			3			—			2			(1	)		1			—			—		—			—		—			—
Settlements or curtailments cost (income)		—			—			—			1			—			(1	)		—			—		—			—		(1	)		—
Other		—			2			—			—			—			—			—			—		—			—		—			—

Net periodic benefit cost	$	3		$	9		$	3		$	8		$	2		$	5		$	—		$	1	$	—		$	1	$	5		$	1

Other changes in plan assets and benefit obligations recognized in other comprehensive income are as follows:


	Years Ended September 30
	2011					2010					2009					2011						2010				2009
	Pension Benefits															Postretirement Benefits
	U.S.		Foreign			U.S.		Foreign			U.S.		Foreign			U.S.			Foreign			U.S.		Foreign		U.S.			Foreign
	(Dollars in millions)
Net losses (gains)	$	2	$	1		$	5	$	12		$	34	$	18			(1	)	$	(1	)	$	1	$	—	$	11		$	2
Prior service cost		—		—			—		—			—		1			(2	)		—			—		—		(17	)		—
Amortization of prior service (cost) credit		—		—			—		—			—		—			4			—			4		—		2			—
Amortization of prior unrecognized (loss) gain		—		(3	)		—		(2	)		1		(1	)		—			—			—		—		—			—
Other		—		—			—		1			—		—			—			—			—		—		—			—

Total other comprehensive loss (income)	$	2	$	(2	)	$	5	$	11		$	35	$	18		$	1		$	(1	)	$	5	$	—	$	(4	)	$	2

Curtailments and settlements of employee benefit plans

In recent years, the Company incurred curtailments and settlements of certain of its employee benefit plans. Associated with these curtailments and settlements, the Company recognized a net gain of less than $1 million, a net loss of $1 million and a net gain of $2 million in fiscal 2011, 2010 and 2009, respectively.

Sensitivity Analysis

Measurement of postretirement benefit expense is based on actuarial assumptions used to value the postretirement benefit liability at the beginning of the year. Assumed health care cost trend rates have an effect on the amounts reported for the health care plans. The fiscal 2011 weighted-average assumed health care cost trend rate is 8.5% for U.S. plans and 8.0% for foreign plans. The ultimate weighted-average health care cost trend rate has been designated as 5% for U.S. plans and 6% for foreign plans and is anticipated to be achieved during 2018 and 2016, respectively. A 1-percentage point change in the 2011 assumed health care cost trend rate would have the following effects:


	1-Percentage-Point
	Increase				Decrease
	U.S.		Foreign		U.S.		Foreign
	(Dollars in millions)
Effect on postretirement benefit obligation	$	—	$	2	$	—	$	(2	)

Plan Assets

The Company's defined benefit pension plans weighted-average asset allocations at September 30, 2011 and 2010, by asset category are as follows:


	Pension Assets
	September 30
	2011						2010
	U.S.			Foreign			U.S.			Foreign
Asset Category:
Equity securities		57	%		44	%		64	%		44	%
Debt securities		43	%		50	%		36	%		51	%
Cash and other securities		—	%		6	%		—	%		5	%

Total		100	%		100	%		100	%		100	%

To develop the expected long-term rate of return on plan assets assumption, the Company used a capital asset pricing model. The model considers the current level of expected returns on risk-free investments comprised of government bonds, the historical level of the risk premium associated with the other asset classes in which the portfolio is invested, and the expectations for future returns for each asset class. The expected return for each asset class was then weighted based on the target asset allocation to develop the expected long-term rate of return for each plan.

Cabot's investment strategy for each of its defined benefit plans in the U.S. and abroad is generally based on a set of investment objectives and policies that cover time horizons and risk tolerance levels consistent with plan liabilities. Periodic studies are performed to determine the asset mix that will meet pension obligations at a reasonable cost to the Company. The assets of the defined benefit plans are comprised principally of investments in equity and high quality fixed income securities, which are broadly diversified across the capitalization and style spectrum and are managed using both active and passive strategies. The weighted average target asset allocation for the U.S. plan is 65% in equity and 35% in fixed income and for the foreign plans is 44% in equity, 51% in fixed income and 5% in cash and other securities.

For pension or other postretirement benefit plan assets classified as Level 1 measurements (measured using quoted prices in active markets), total fair value is either the price of the most recent trade at the time of the market close or the official close price, as defined by the exchange on which the asset is most actively traded on the last trading day of the period, multiplied by the number of units held without consideration of transaction costs.

For pension or other postretirement benefit plan assets classified as Level 2 measurements, where the security is frequently traded in less active markets, fair value is based on the closing price at the end of the period; where the security is less frequently traded, fair value is based on the price a dealer would pay for the security or similar securities, adjusted for any terms specific to that asset or liability. Market inputs are obtained from well-established and recognized vendors of market data and subjected to tolerance/quality checks.

Some pension or other postretirement benefit plan assets are held in funds where a net asset value is calculated based on the fair value of the underlying assets and the number of shares owned. The classification of the fund (Level 1, 2 or 3 measurements) is determined based on the classification of the significant holdings within the fund. For all other pension or other postretirement benefit plan assets for which observable inputs are used, fair value is derived through the use of fair value models, such as a discounted cash flow model or other standard pricing models.

The fair value of the Company's pension plan assets at September 30, 2011 by asset category is as follows:


			Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Observable Inputs (Level 2)		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Observable Inputs (Level 2)
	Total		US				Non-US
	(Dollars in millions)
Asset Category:
Cash and cash equivalents	$	5	$	—	$	1	$	4	$	—
Direct investments:
U.S. equity securities		13		13		—		—		—
Non-U.S. equity securities		1		1		—		—		—
Non-U.S. government bonds		47		—		—		47		—
Non-U.S. corporate bonds		1		—		—		1		—

Total direct investments		62		14		—		48		—
Investment funds:
Equity funds⁽¹⁾		106		20		—		—		86
Fixed income funds⁽²⁾		93		43		—		—		50
Real estate funds⁽³⁾		1		—		—		—		1
Common and collective investment trust fund⁽⁴⁾		24		—		24		—		—
Money market fund		1		1		—		—		—

Total investment funds		225		64		24		—		137
Alternative investments:
Insurance contracts		8		—		—		—		8

Total alternative investments		8		—		—		—		8

Total pension plan assets	$	300	$	78	$	25	$	52	$	145

⁽¹⁾	The equity funds asset class includes funds that invest in U.S. equities as well as equity securities issued by companies incorporated, listed or domiciled in countries in developed and/or emerging markets. These companies may be in the small-, mid- or large-cap categories.

⁽²⁾

The fixed income funds asset class includes investments in high quality funds. High quality fixed income funds primarily invest in low risk U.S. and non-U.S. government securities, investment-grade corporate bonds, mortgages and asset-backed securities. A significant portion of the fixed income funds asset includes investment in long-term bond funds.

⁽³⁾

The real estate funds asset class includes funds that primarily invest in entities which are principally engaged in the ownership, acquisition, development, financing, sale and/or management of income-producing real estate properties, both commercial and residential. These funds typically seek long-term growth of capital and current income that is above average relative to public equity funds.

⁽⁴⁾

The investment objective of the portfolio of this common and collective investment trust is to achieve long-term, total return in excess of the MSCI World Index Benchmark by investing in equity securities of companies worldwide, emphasizing those with above-average potential for capital appreciation.

Tabular disclosure of one or more of the entity's defined benefit pension plans or one or more other defined benefit postretirement plans, separately for pension plans and other postretirement benefit plans including the entity's schedule of fair value of plan assets for defined benefit or other postretirement plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5, 6, 7
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 158
-Paragraph 4, 7, 16, 20, 21
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=6930749&loc=d3e4179-114921

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2410-114920

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2439-114920

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2417-114920

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Stock-Based Compensation

12 Months Ended

Sep. 30, 2011

Stock Based Compensation

Stock Based Compensation

Note O. Stock-Based Compensation

The Company has established equity compensation plans that provide stock-based compensation to eligible employees. The 2009 Long-Term Incentive Plan (the "2009 Plan"), which was approved by Cabot's stockholders on March 12, 2009, authorizes the issuance of 6.4 million shares of common stock. This is the Company's only equity incentive plan under which awards may currently be made to employees, although some awards made under the Company's 2006 Long-Term Incentive Plan (the "2006 Plan") remain outstanding at September 30, 2011.

The terms of awards made under Cabot's equity compensation plans are generally determined by the Compensation Committee of Cabot's Board of Directors. The 2009 Plan allows for grants of stock options, restricted stock, restricted stock units and other stock-based awards to employees. The awards made in fiscal 2011, 2010 and 2009 under the 2009 Plan consisted of grants of stock options, time-based restricted stock units, and performance-based restricted stock units. The options were issued with an exercise price equal to 100% of the market price of Cabot's common stock on the date of grant, vest over a three year period (30% on each of the first and second anniversaries of the date of grant and 40% on the third anniversary of the date of grant) and expire ten years after grant. The restricted stock units vest three years from the date of the grant. The number of shares issuable, if any, when a performance-based restricted stock unit award vests will depend on the degree of achievement ( threshold, target or maximum performance) of the corporate performance metrics for each year within the three-year performance period of the award. Accordingly, future compensation costs associated with outstanding awards of performance-based restricted stock units may increase or decrease based on the probability of the Company achieving the performance metrics.

Prior to 2009, the principal awards made under the Company's equity plans consisted of grants of restricted stock and stock options. The shares of restricted stock were generally purchased by the employee at a price equal to 30% of the market price of Cabot's common stock on the date of grant, with vesting dates three years after the date of grant. The stock options issued prior to 2009 were issued with an exercise price equal to 100% of the market price of Cabot's common stock on the date of grant, vest three years after the date of grant and expire five years after grant.

With respect to the shares of restricted stock issued prior to 2009, in many instances, the Company provided loans to employees, other than executive officers, to facilitate their purchase of the shares. These loans are full recourse, secured by the purchased shares, have a term of approximately three years, and accrue interest at market rates. During the third quarter of fiscal 2009, the Company extended the maturity date of the loans made in 2006 by thirty-six months to August 2012. After evaluating the facts and circumstances related to these loans, in 2009, the Company determined that it was appropriate to apply option accounting to all unvested restricted stock awards under the 2006 Plan that had accompanying loans. In fiscal 2009, total incremental stock-based compensation expense related to this change was $4 million, and was being recorded over the remaining vesting period that ended in May 2011. As of September 30, 2011 and 2010, the outstanding loan balances were $2 million and $8 million, respectively. Prior to extending the maturity of the loans made in May 2006, all of the loans were recorded in equity. Subsequent to this event, the loans have been removed from the balance sheet as all of the restricted stock awards with Company loans are accounted for as if they were stock options.

Stock-based employee compensation expense was $10 million, $11 million and $12 million, after tax, for fiscal 2011, 2010 and 2009, respectively. The Company recognized the full impact of its stock-based employee compensation expense in the Consolidated Statements of Operations for fiscal 2011, 2010 and 2009 and did not capitalize any such costs on the Consolidated Balance Sheets because those that qualified for capitalization were not material. The following table presents stock-based compensation expenses included in the Company's Consolidated Statement of Operations:


	Years Ended September 30
	2011			2010			2009
	(Dollars in millions)
Cost of Sales	$	5		$	6		$	7
Selling and administrative expenses		9			11			11
Research and technical expenses		1			1			1

Stock-based compensation expense		15			18			19
Income tax benefit		(5	)		(7	)		(7	)

Net stock-based compensation expense	$	10		$	11		$	12

As of September 30, 2011, Cabot has $14 million, $2 million and less than $1 million of total unrecognized compensation cost related to non-vested restricted stock units, non-vested options and non-vested restricted stock, respectively, granted under the Company's equity incentive plans. That cost is expected to be recognized over a weighted-average period of 1.6 years, 0.8 years and 0.4 years for non-vested restricted stock units, non-vested options and the non-vested restricted stock, respectively.

Equity Incentive Plan Activity

The following table summarizes the total stock option, restricted stock, and restricted stock unit activity in the equity incentive plans for fiscal 2011:


	September 30, 2011
	Stock Options							Restricted Stock					Restricted Stock Units
	Total Options			Weighted Average Exercise Price		Weighted Average Grant Date Fair Value		Restricted Stock			Weighted Average Grant Date Fair Value		Restricted Stock Units⁽¹⁾			Weighted Average Grant Date Fair Value
	(Shares in thousands)
Outstanding at September 30, 2010		1,765		$	20.40	$	5.21		829		$	20.81		454		$	23.90
Granted		250			34.64		12.09		—			—		387			34.76
Performance-based adjustment⁽²⁾		—			—		—		—			—		58			28.60
Exercised / Vested		(180	)		23.32		5.67		(820	)		22.61		(4	)		28.63
Cancelled / Forfeited		(63	)		24.74		7.35		(6	)		22.43		(29	)		28.48

Outstanding at September 30, 2011		1,772			21.96		6.06		3			9.56		866			28.89

Exercisable at September 30, 2011		809			20.70

Expected to vest⁽³⁾		940			23.07

⁽¹⁾

The number "Granted" represents the number of shares issuable upon vesting of time-based restricted stock units and performance-based restricted stock units, assuming the Company performs at the target performance level in each year of the three-year performance period. Restricted stock units outstanding as of September 30, 2010 have been recast to include the incremental number of shares issuable upon vesting of outstanding performance-based restricted stock units, based on the Company achieving performance at a level greater than target under the 2010 performance targets.

⁽²⁾	Represents the incremental number of shares issuable upon vesting of outstanding performance-based restricted stock units, based on the Company achieving performance at a level greater than target under the 2011 performance targets.

⁽³⁾	Stock options expected to vest in the future, net of estimated forfeitures, have a weighted average remaining contractual life of 8.1 years.

Stock Options

The following table summarizes information related to the outstanding and vested options on September 30, 2011:


	Total Options Outstanding		Exercisable Options
Aggregate Intrinsic Value (in millions)	$	5	$	3
Weighted Average Remaining Contractual Term (in years)		7.5		6.7

The aggregate intrinsic value in the table above represents the total pre-tax intrinsic value, based on the Company's closing common stock price of $24.78 on September 30, 2011, which would have been received by the option holders had all option holders exercised their options and immediately sold their shares on that date.

The intrinsic value of options exercised during fiscal 2011 and 2010 was $3 million and $1 million, respectively, and the Company received cash of $4 million and $3 million, respectively, from these exercises. No options were exercised in fiscal 2009.

Approximately 612,000, 441,000 and 79,000 options vested during fiscal 2011, 2010 and 2009, respectively. The weighted average grant date fair value of these options was $3 million, $2 million and $1 million, respectively. The Company uses the Black-Scholes option-pricing model to estimate the fair value of the options at the grant date. The estimated weighted average grant date fair values of options granted during fiscal 2011, 2010 and 2009 was $12.09, $7.41, and $3.98 per option, respectively. The fair values on the grant date (including the application of option accounting to the restricted stock awards as noted previously) were calculated using the following weighted-average assumptions:


	Years Ended September 30
	2011			2010			2009
Expected stock price volatility		43	%		42	%		39	%
Risk free interest rate		1.8	%		2.8	%		0.4	%
Expected life of options (years)		6			6			6
Expected annual dividends per year	$	0.72		$	0.72		$	0.72

The expected stock price volatility assumption was determined using the historical volatility of the Company's common stock over the expected life of the option.

Restricted Stock Units

The value of restricted stock unit awards is the closing stock price at the date of the grant. The estimated weighted average grant date fair values of restricted stock unit awards granted during fiscal 2011 and 2010 was $34.76 and $24.49, respectively. There were no restricted stock unit awards granted during fiscal 2009. The intrinsic value of restricted stock units that vested during fiscal 2011 was less than $1 million. No restricted stock units vested during fiscal 2010 or 2009.

Restricted Stock

The fair value of restricted stock awards is derived by calculating the difference between the share price and the purchase price at the date of the grant. The estimated weighted average grant date fair values of restricted stock awards granted during fiscal 2009 were $9.56. There were no restricted stock awards granted during fiscal 2011 or 2010. The intrinsic value of restricted stock that vested during fiscal 2011, 2010 and 2009 was $27 million, $11 million and $5 million, respectively.

Supplemental Retirement Savings Plan

Cabot's SRSP provides benefits to highly compensated employees in circumstances in which the maximum limits established under ERISA and the Internal Revenue Code prevent them from receiving all of the Company matching and ESOP contributions that would otherwise be provided under the qualified RSP. The SRSP is non-qualified and unfunded. Contributions under the SRSP are treated as if invested in Cabot common stock. The majority of the distributions made under the SRSP are required to be paid with shares of Cabot common stock. The remaining distributions, which relate to certain grandfathered accounts, will be paid in cash based on the market price of Cabot common stock at the time of distribution. The aggregate value of the accounts that will be paid out in stock, which is equivalent to approximately 125,000 and 166,000 shares of Cabot common stock as of September 30, 2011 and 2010, respectively, is reflected at historic cost in stockholders' equity, and the aggregate value of the accounts that will be paid in cash, which is $1 million as of both September 30, 2011 and 2010, is reflected in other long-term liabilities and marked-to-market quarterly.

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64, 65, A240
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 93-6
-Paragraph 53
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 50
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6406099&loc=d3e25284-112666

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 6: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5444-113901

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6418621&loc=d3e17540-113929

Restructuring

12 Months Ended

Sep. 30, 2011

Restructuring

Restructuring

Note P. Restructuring

Cabot's restructuring activities were recorded in the Consolidated Statements of Operations as follows:


	Years Ended September 30
	2011		2010		2009
	(Dollars in millions)
Cost of sales	$	16	$	36	$	80
Selling and administrative expenses		2		10		5
Research and technical expenses		—		—		2

Total	$	18	$	46	$	87

Details of these restructuring activities and the related reserves for fiscal 2011 and 2010 were as follows:


	Severance and Employee Benefits			Environmental Remediation			Asset Impairment and Accelerated Depreciation			Asset Sales			Other			Total
	(Dollars in millions)
Reserve at September 30, 2009	$	20		$	1		$	—		$	—		$	—		$	21
Charges		29			2			11			(3	)		7			46
Costs charged against assets and other		—			—			(11	)		—			—			(11	)
Proceeds from sale		—			—			—			3			—			3
Cash paid		(27	)		(2	)		—			—			(7	)		(36	)
Foreign currency translation adjustment		(4	)		—			—			—			—			(4	)

Reserve at September 30, 2010	$	18		$	1		$	—		$	—		$	—		$	19
Charges		8			3			3			(1	)		5			18
Costs charged against assets and other		1			—			(3	)		(4	)		—			(6	)
Proceeds from sale		—			—			—			6			—			6
Cash paid		(17	)		(4	)		—			(1	)		(4	)		(26	)
Foreign currency translation adjustment		(1	)		—			—			—			1			—

Reserve at September 30, 2011	$	9		$	—		$	—		$	—		$	2		$	11

Closure of Grigno, Italy Manufacturing Facility and Other Activities

In February 2011, the Company closed its thermoplastic concentrates manufacturing facility in Grigno, Italy. This decision was made to align Cabot's manufacturing capabilities with the market outlook and Cabot's Performance Segment strategy. The closure, which affected 37 employees, resulted in $6 million of charges to earnings and is comprised of $3 million for severance and employee benefits and $3 million for accelerated depreciation and asset impairments.

Through September 30, 2011, Cabot made $1 million of cash payments associated with this restructuring plan. The Company expects to make additional cash payments of $2 million in 2012.

As of September 30, 2011, Cabot has $2 million of accrued restructuring costs in the Consolidated Balance Sheet related to this site closure.

In addition, during fiscal 2011 Cabot recorded approximately $5 million of other severance-related restructuring charges at other locations around the world. Cabot expects $4 million to be paid in fiscal 2012 and $1 million to be paid in fiscal 2013 related to these activities.

Closure of Thane, India Manufacturing Facility

In fiscal 2010, Cabot ceased manufacturing operations at its carbon black manufacturing facility in Thane, India. This decision, which affected approximately 120 employees, was made as a result of a broad reaching analysis of the Company's manufacturing assets, including their cost structure, ability to expand and a variety of other factors. The Company continues to maintain a presence in India through its fumed metal oxides manufacturing joint venture and continuing commercial operations in carbon black and other products.

The Company expects the closure plan will result in a total pre-tax charge to earnings of approximately $20 million. Through September 30, 2011, Cabot has recorded $19 million of charges associated with this restructuring, comprised of $7 million for severance and employee benefits, $10 million for accelerated depreciation and asset impairments, $1 million for demolition and site clearing costs and $2 million for other post-closing costs offset by a net gain on sales of non-manufacturing related assets of approximately $1 million. These amounts exclude any potential gain to be recognized on the sale of land and certain other manufacturing related assets.

Cumulative net cash outlays related to this plan are expected to be approximately $7 million. Through fiscal 2011, Cabot has made net cash payments of $7 million. The Company expects to make cash payments of $1 million in 2012 offset by anticipated cash receipts on non-manufacturing related asset sales of $1 million. These amounts exclude any potential cash to be received on the sale of land and certain other manufacturing related assets.

As of September 30, 2011, Cabot has $1 million of accrued restructuring costs in the Consolidated Balance Sheet related to this site closure.

2009 Global Restructuring

In fiscal 2009, Cabot initiated its 2009 Global Restructuring Plan. Under this plan, the Company closed three manufacturing sites and implemented operating cost and workforce reductions across a variety of its other operations. In fiscal 2010, the Company consolidated several of its European administrative offices in a new European headquarters office in Switzerland.

The Company has recorded a cumulative pre-tax charge of $120 million. In addition, the Company expects to recognize a gain on sale related to one of its former manufacturing sites in fiscal 2012. The total amounts the Company has recorded for each major type of cost associated with the restructuring plan are: (i) severance and employee benefits of $54 million for approximately 400 employees, (ii) accelerated depreciation and impairment of facility assets of $45 million, net of gains associated with the sale of certain assets, (iii) demolition and site clearing costs of $6 million, and (iv) other post-closing costs of $15 million. Net cash outlays related to these actions are expected to be approximately $68 million. Through fiscal 2011, Cabot has made net cash payments of $68 million. In 2012 and thereafter the Company expects to make severance and related payments totaling $3 million offset by the expected proceeds on sale of a former manufacturing site.

As of September 30, 2011, Cabot has $3 million of restructuring costs in accrued expenses in the Consolidated Balance Sheet related to this plan.

The entire disclosure for restructuring and related activities. Description of restructuring activities such as exit and disposal activities, include facts and circumstances leading to the plan, the expected plan completion date, the major types of costs associated with the plan activities, total expected costs, the accrual balance at the end of the period, and the periods over which the remaining accrual will be settled.

Stockholders' Equity

12 Months Ended

Sep. 30, 2011

Stockholders' Equity

Stockholders' Equity

Note Q. Stockholders' Equity

In fiscal 2007, the Board of Directors authorized Cabot to repurchase up to ten million shares of Cabot's common stock in the open market or in privately negotiated transactions. This authorization does not have a set expiration date. Under this authorization, the Company repurchased approximately 1.6 million shares in fiscal 2011, no shares in fiscal 2010 and approximately 3,500 shares in fiscal 2009. As of September 30, 2011, approximately 2.7 million shares remain available for repurchase under the current authorization.

During each of fiscal 2011, 2010 and 2009, Cabot paid cash dividends of $0.72 per share of common stock.

Accumulated Other Comprehensive Income

The following table illustrates the after-tax balances of the components comprising Accumulated other comprehensive income:


	September 30
	2011			2010
	(Dollars in millions)
Foreign currency translation adjustments	$	163		$	144
Unrealized holding gain on investments		1			1
Change in funded status of retirement plans		(58	)		(57	)

Accumulated other comprehensive income	$	106		$	88

The entire disclosure for shareholders' equity, comprised of portions attributable to the parent entity and noncontrolling interest, if any, including other comprehensive income (as applicable). Including, but not limited to: (1) balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings; (2) accumulated balance for each classification of other comprehensive income and total amount of comprehensive income; (3) amount and nature of changes in separate accounts, including the number of shares authorized and outstanding, number of shares issued upon exercise and conversion, and for other comprehensive income, the adjustments for reclassifications to net income; (4) rights and privileges of each class of stock authorized; (5) basis of treasury stock, if other than cost, and amounts paid and accounting treatment for treasury stock purchased significantly in excess of market; (6) dividends paid or payable per share and in the aggregate for each class of stock for each period presented; (7) dividend restrictions and accumulated preferred dividends in arrears (in aggregate and per share amount); (8) retained earnings appropriations or restrictions, such as dividend restrictions; (9) impact of change in accounting principle, initial adoption of new accounting principle and correction of an error in previously issued financial statements; (10) shares held in trust for Employee Stock Ownership Plan (ESOP); (11) deferred compensation related to issuance of capital stock; (12) note received for issuance of stock; (13) unamortized discount on shares; (14) description, terms, and number of warrants or rights outstanding; (15) shares under subscription and subscription receivables, effective date of new retained earnings after quasi-reorganization and deficit eliminated by quasi-reorganization and, for a period of at least ten years after the effective date, the point in time from which the new retained dates; and (16) retroactive effective of subsequent change in capital structure.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
-Number 210
-Article 4
-Section 08
-Paragraph d

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 1
-Section B
-Paragraph 7, 11A
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 129
-Paragraph 2, 3, 4, 5, 6, 7, 8
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30, 31
-Article 5

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section E

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section C

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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Reference 12: http://www.xbrl.org/2003/role/presentationRef
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Reference 15: http://www.xbrl.org/2003/role/presentationRef
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Reference 16: http://www.xbrl.org/2003/role/presentationRef
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Reference 17: http://www.xbrl.org/2003/role/presentationRef
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-Subparagraph (SX 210.4-08.(d),(e))
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Reference 21: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Preferred Stock
-URI http://asc.fasb.org/extlink&oid=6521494

Reference 22: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.5-02.29-31)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 23: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187143-122770

Earnings Per Share

12 Months Ended

Sep. 30, 2011

Earnings Per Share

Earnings Per Share

Note R. Earnings Per Share

The following tables summarize the components of the basic and diluted earnings per common share computations:


	Years Ended September 30
	2011			2010			2009
	(In millions, except per share amounts)
Basic EPS:
Net income (loss) attributable to Cabot Corporation	$	236		$	154		$	(77	)
Less: Dividends and dividend equivalents to participating securities		1			1			2
Less: Undistributed earnings allocated to participating securities⁽¹⁾		2			2			—

Earnings (loss) allocated to common shareholders (numerator)	$	233		$	151		$	(79	)

Weighted average common shares and participating securities outstanding		65.4			65.3			65.3
Less: Participating securities⁽¹⁾		0.8			1.5			2.5

Adjusted weighted average common shares (denominator)		64.6			63.8			62.8

Per share amounts—basic:
Income (loss) from continuing operations attributable to Cabot Corporation	$	2.80		$	1.96		$	(1.21	)
Income (loss) from discontinued operations		0.82			0.41			(0.04	)

Net income (loss) attributable to Cabot Corporation	$	3.62		$	2.37		$	(1.25	)

Diluted EPS:
Earnings (loss) allocated to common shareholders	$	233		$	151		$	(79	)
Plus: Earnings allocated to participating securities		3			3			2
Less: Adjusted earnings allocated to participating securities⁽²⁾		(3	)		(3	)		(2	)

Earnings (loss) available to common shares (numerator)	$	233		$	151		$	(79	)

Adjusted weighted average common shares outstanding		64.6			63.8			62.8
Effect of dilutive securities:
Common shares issuable⁽³⁾		0.8			0.5			—

Adjusted weighted average common shares (denominator)		65.4			64.3			62.8

Per share amounts—diluted:
Income (loss) from continuing operations attributable to Cabot Corporation	$	2.77		$	1.94		$	(1.21	)
Income (loss) from discontinued operations		0.80			0.41			(0.04	)

Net income (loss) attributable to Cabot Corporation	$	3.57		$	2.35		$	(1.25	)

⁽¹⁾

Participating securities consist of shares of unvested restricted stock, vested restricted stock awards held by employees in which Cabot has a security interest, and unvested time-based restricted stock units.

Undistributed earnings are the earnings which remain after dividends declared during the period are assumed to be distributed to the common and participating shareholders. Undistributed earnings are allocated to common and participating shareholders on the same basis as dividend distributions. The calculation of undistributed earnings is as follows:


	Years Ended September 30
	2011		2010		2009
	(Dollars in millions)
Calculation of undistributed earnings:
Net income (loss) attributable to Cabot Corporation	$	236	$	154	$	(77	)
Less: Dividends declared on common stock		46		46		46
Less: Dividends and dividend equivalents to participating securities		1		1		2

Undistributed earnings	$	189	$	107	$	(125	)

Allocation of undistributed earnings:
Undistributed earnings allocated to common shareholders	$	187	$	105	$	(125	)
Undistributed earnings allocated to participating securities		2		2		—

Undistributed earnings	$	189	$	107	$	(125	)

⁽²⁾

Undistributed earnings are adjusted for the assumed distribution of dividends to the dilutive securities, which are described in (3) below, and then reallocated to participating securities.

⁽³⁾

Represents incremental shares of common stock from the (i) assumed exercise of stock options issued under Cabot's equity incentive plans; (ii) assumed issuance of shares to employees pursuant to the Company's Supplemental Retirement Savings Plan; and (iii) assumed issuance of shares for outstanding and achieved performance-based stock unit awards issued under Cabot's equity incentive plans using the treasury stock method. For fiscal 2011, 253,000 incremental shares of common stock were not included in the calculation of diluted earnings per share because the inclusion of these shares would have been antidilutive. For fiscal 2010, 193,000 incremental shares of common stock were not included in the calculation of diluted earnings per share because those shares' exercise prices were greater than the average market price of Cabot common stock for that period. For fiscal 2009, 3,833,000 incremental shares of common stock were excluded from the calculation of diluted earnings per share as those shares would have been antidilutive due to the Company's net loss position.

Income Taxes

12 Months Ended

Sep. 30, 2011

Income Taxes

Income Taxes

Note S. Income Taxes

Income (loss) from continuing operations before income taxes and equity in net earnings of affiliated companies was as follows:


	Years ended September 30
	2011			2010		2009
	(Dollars in millions)
Domestic	$	(25	)	$	3	$	(72	)
Foreign		228			163		(27	)

Total	$	203		$	166	$	(99	)

Tax provision (benefit) on income (loss) consisted of the following:


	Years ended September 30
	2011			2010			2009
	(Dollars in millions)
U.S. federal and state:
Current	$	(7	)	$	(8	)	$	(2	)
Deferred		(51	)		(14	)		(32	)

Total		(58	)		(22	)		(34	)

Foreign:
Current		57			51			27
Deferred		7			1			(14	)

Total		64			52			13

Total U.S. and foreign	$	6		$	30		$	(21	)

The provision (benefit) for income taxes differed from the provision for income taxes as calculated using the U.S. statutory rate as follows:


	Years ended September 30
	2011			2010			2009
	(Dollars in millions)
Computed tax expense at the federal statutory rate	$	70		$	58		$	(35	)
Foreign income:
Impact of taxation at different rates, repatriation and other		(29	)		(26	)		(3	)
Impact of repatriation of high tax income		(24	)		—			—
Impact of investment incentive credits		(2	)		(2	)		(1	)
Impact of foreign losses for which a current tax benefit is not available		6			17			30
State taxes, net of federal effect		—			—			—
U.S. and state benefits from research and experimentation activities		(3	)		(1	)		(4	)
Tax audit settlements		(12	)		(15	)		(9	)
Other, net		—			(1	)		1

Total	$	6		$	30		$	(21	)

Significant components of deferred income taxes were as follows:


	September 30
	2011			2010
	(Dollars in millions)
Deferred tax assets:
Depreciation and amortization	$	73		$	67
Pension and other benefits		87			89
Environmental liabilities		3			3
Inventory		12			16
Deferred expenses		11			15
Net operating loss carry-forwards		125			131
Other tax carry-forwards		137			95
Other		28			26

Subtotal		476			442
Valuation allowances		(138	)		(126	)

Total deferred tax assets	$	338		$	316

	September 30
	2011			2010
	(Dollars in millions)
Deferred tax liabilities:
Depreciation and amortization	$	28		$	28
Pension and other benefits		2			4
Unremitted earnings of non-U.S. subsidiaries		18			12
Inventory		3			3
Other		5			6

Total deferred tax liabilities	$	56		$	53

In fiscal 2011, Cabot recorded $38 million net tax benefits including $24 million from the repatriation of high taxed income and $14 million related to tax settlements, the renewal of the U.S. research and experimentation credit, and investment incentive tax credits in the tax provision.

In fiscal 2010, Cabot recorded $17 million of net tax benefits related to tax settlements and investment incentive tax credits and a $1 million net tax charge for other miscellaneous items in the tax provision.

In fiscal 2009, Cabot recorded $12 million of net tax benefits related to tax settlements, the renewal of the U.S. research and experimentation credit, and investment incentive tax credits in the tax provision.

Approximately $565 million of net operating loss carryforwards ("NOLs") and $137 million of other tax credit carryforwards remain at September 30, 2011. The benefits of these carryforwards are dependent upon taxable income during the carryforward period in the jurisdictions where they arose. Accordingly, a valuation allowance has been provided where management has determined that it is more likely than not that the carryforwards will not be utilized. The following table provides detail surrounding the expiration dates of these carryforwards:


	NOLs		Other Credits
	(Dollars in millions)
Expiration periods
2012 to 2018	$	132	$	6
2019 and thereafter		131		110
Indefinite carryforward		302		21

Total	$	565	$	137

As of September 30, 2011, provisions have not been made for U.S. income taxes or non-U.S. withholding taxes on approximately $887 million of undistributed earnings of non-U.S. subsidiaries, as these earnings are considered indefinitely reinvested. These earnings could become subject to U.S. income taxes and non-U.S. withholding taxes if they were remitted as dividends, were loaned to Cabot Corporation or a U.S. subsidiary, or if Cabot should sell its stock in the subsidiaries.

As of September 30, 2011, Cabot has net deferred tax assets of $282 million, $247 million of which are in the U.S. Management believes that the Company's history of generating domestic profits provides adequate evidence that it is more likely than not that all of the U.S. net deferred tax assets will be realized in the normal course of business. U.S. income (loss) from continuing operations adjusted for U.S. permanent differences was a profit of $86 million for the year ended September 30, 2011 and was a cumulative profit of $131 million for the three years ended September 30, 2011.

Realization of the tax asset is dependent on achieving the forecast of future taxable operating income over an extended period of time. As of September 30, 2011, the Company would need to generate approximately $706 million in cumulative future U.S. taxable operating income at various times over approximately 20 years to realize all of its net U.S. deferred tax assets. The Company also believes that it is more likely than not that Cabot will recover the $35 million non-U.S. net deferred tax asset which will require approximately $117 million of future taxable operating income to be generated by various non-U.S. subsidiaries given the subsidiaries' history of profitability. The Company reviews its forecast in relation to actual results and expected trends on a quarterly basis. Failure to achieve operating income targets may change the Company's assessment regarding the recoverability of Cabot's deferred tax assets and such change could result in a valuation allowance being recorded against some or all of the Company's deferred tax assets. Any increase in a valuation allowance would result in additional income tax expense, lower stockholders' equity and could have a significant impact on Cabot's earnings in future periods.

The valuation allowances at September 30, 2011 and 2010 represent management's best estimate of the non-realizable portion of the deferred tax assets. The valuation allowance increased in certain tax jurisdictions by $12 million, $6 million, and $33 million in fiscal years 2011, 2010 and 2009, respectively, due to the uncertainty of the ultimate realization of certain future tax benefits and net operating losses reflected as deferred tax assets.

Cabot has filed its tax returns in accordance with the tax laws in each jurisdiction and recognizes tax benefits for uncertain tax positions when the position would more likely than not be sustained based on its technical merits and recognizes measurement adjustments when needed. As of September 30, 2011, the total amount of unrecognized tax benefits was $65 million, of which $39 million was recorded in the Company's Consolidated Balance Sheet and $26 million, principally related to state net operating loss carryforwards, have not been recorded. In addition, accruals of $3 million and $14 million have been recorded for penalties and interest, respectively, as of September 30, 2011. Total penalties and interest recorded in the tax provision was $3 million in each of fiscal years 2011, 2010, and 2009. If the unrecognized tax benefits were recognized at a given point in time, there would be approximately $56 million favorable impact on the Company's tax provision.

A reconciliation of the beginning and ending amount of unrecognized tax benefits for fiscal 2011, 2010 and 2009 are as follows:


	Years ended September 30
	2011			2010			2009
	(Dollars in millions)
Balance at beginning of the year	$	75		$	81		$	80
Additions based on tax provisions related to the current year		2			6			7
Additions for tax positions of prior years		1			3			4
Reductions of tax provisions of prior years		(13	)		(15	)		(10	)

Balance at end of the year	$	65		$	75		$	81

During fiscal 2011, the balance of unrecognized tax benefits was reduced by $13 million primarily due to the settlement of audits in a number of tax jurisdictions including a settlement recorded in income from discontinued operations, net of tax, in the Consolidated Statement of Operations. Certain Cabot subsidiaries are under audit in jurisdictions outside of the U.S. In addition, certain statutes of limitations are scheduled to expire in the near future. It is reasonably possible that a further change in the unrecognized tax benefits may occur within the next twelve months related to the settlement of one or more of these audits or the lapse of applicable statutes of limitations; however, an estimated range of the impact on the unrecognized tax benefits cannot be quantified at this time.

Cabot files U.S. federal and state and non-U.S. income tax returns in jurisdictions with varying statutes of limitations. The 2007 through 2011 tax years generally remain subject to examination by the IRS and the 2004 through 2011 tax years remain subject to examination by most state tax authorities. In significant non-U.S. jurisdictions, the 2005 through 2011 tax years generally remain subject to examination by their respective tax authorities with the exception of Canada and the United Kingdom which are open from 2001. Cabot's significant non-U.S. jurisdictions include Argentina, Brazil, Canada, China, Germany, Japan, the Netherlands, and the United Kingdom.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 136, 172
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 43, 44, 45, 46, 47, 48, 49
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319

Commitments And Contingencies

Commitments And Contingencies

12 Months Ended

Sep. 30, 2011

Commitments And Contingencies

Note T. Commitments and Contingencies

Operating Lease Commitments

Cabot leases certain transportation vehicles, warehouse facilities, office space, machinery and equipment under cancelable and non-cancelable operating leases, most of which expire within ten years and may be renewed by Cabot. Escalation clauses, lease payments dependent on existing rates/indexes and other lease concessions are included in the minimum lease payments and such lease payments are recognized on a straight-line basis over the minimum lease term. Rent expense under such arrangements for fiscal 2011, 2010 and 2009 totaled $19 million, $21 million and $27 million, respectively. Future minimum rental commitments under non-cancelable leases are as follows:


	(Dollars in millions)
2012		19
2013		15
2014		12
2015		11
2016		8
2017 and thereafter		29

Total future minimum rental commitments	$	94

Other Long-Term Commitments

Cabot has entered into long-term purchase agreements primarily for the purchase of raw materials. Under certain of these agreements, the quantity of material being purchased is fixed, but the prices paid change as market prices change. Raw materials purchased under these agreements by segment for fiscal 2011, 2010 and 2009 are as follows:


	Years Ended September 30
	2011		2010		2009
	(Dollars in millions)
Core Segment	$	340	$	294	$	136
Performance Segment		18		36		82
Specialty Fluids Segment		—		6		4

Total	$	358	$	336	$	222

Included in the table above are raw materials purchases from noncontrolling shareholders of consolidated subsidiaries. These purchases were $134 million, $126 million and $57 million during fiscal 2011, 2010 and 2009, respectively, and as of both September 30, 2011 and 2010, accounts payable and accrued liabilities owed to noncontrolling shareholders was $10 million.

The purchase commitments for the Rubber Blacks Business, Performance Segment and New Business Segment covered by these agreements are with various suppliers and purchases are expected to take place as follows:


	Payments Due by Fiscal Year
	2012		2013		2014		2015		2016		Thereafter		Total
	(Dollars in millions)
Core Segment	$	272	$	245	$	229	$	227	$	200	$	2,705	$	3,878
Performance Segment		16		30		31		30		171		133		411
New Business Segment		1		1		—		—		—		—		2

Total	$	289	$	276	$	260	$	257	$	371	$	2,838	$	4,291

The dollar value of these commitments has been estimated using current market prices. As noted above, these will fluctuate based on time of purchase.

Guarantee Agreements

Cabot has provided certain indemnities pursuant to which it may be required to make payments to an indemnified party in connection with certain transactions and agreements. In connection with certain acquisitions and divestitures, Cabot has provided routine indemnities with respect to such matters as environmental, tax, insurance, product and employee liabilities. In connection with various other agreements, including service and supply agreements, Cabot has provided indemnities for certain contingencies and routine warranties. Cabot is unable to estimate the maximum potential liability for these types of indemnities as a maximum obligation is not explicitly stated in most cases and the amounts, if any, are dependent upon the outcome of future contingent events, the nature and likelihood of which cannot be reasonably estimated. The duration of the indemnities vary, and in many cases are indefinite. Cabot has not recorded any liability for these indemnities in the consolidated financial statements, except as otherwise disclosed.

Self-Insurance and Retention for Certain Contingencies

The Company is partially self-insured for certain third-party liabilities globally, as well as workers' compensation and employee medical benefits in the United States. The third-party and workers' compensation liabilities are managed through a wholly-owned insurance captive and the related liabilities are included in the consolidated financial statements. The employee medical obligations are managed by a third-party provider and the related liabilities are included in the consolidated financial statements. To limit Cabot's potential liabilities for these risks, however, the Company purchases insurance from third-parties that provides individual and aggregate stop-loss protection. The aggregate self-insured liability in fiscal 2011 for combined third-party liabilities, U.S. workers' compensation and employee medical benefits was $6 million, and the retention for medical costs in the United States is at most $200,000 per person per annum.

Contingencies

Cabot is a defendant, or potentially responsible party, in various lawsuits and environmental proceedings wherein substantial amounts are claimed or at issue.

Environmental Matters

As of September 30, 2011 and 2010, Cabot had $6 million and $7 million, respectively, reserved for environmental matters primarily related to divested businesses. In fiscal 2011 and 2010, there was $2 million and $2 million in accrued expenses and $4 million and $5 million in other liabilities, respectively, in the consolidated balance sheets for environmental matters. These amounts represent Cabot's best estimates of its share of costs likely to be incurred at those sites where costs are reasonably estimable based on its analysis of the extent of clean up required, alternative clean up methods available, abilities of other responsible parties to contribute and its interpretation of laws and regulations applicable to each site. Cabot reviews the adequacy of this reserve as circumstances change at individual sites. Charges for environmental expense were $1 million, $3 million, and less than $1 million in fiscal 2011, 2010 and 2009, respectively. Cash payments were $2 million, $1 million and $3 million during fiscal 2011, 2010 and 2009, respectively, related to these environmental matters.

The operation and maintenance component of the $6 million reserve for environmental matters was $3 million. Cabot expects to make payments of $1 million in fiscal 2012, $1 million in each of fiscal 2013 through fiscal 2016, and a total of $1 million thereafter.

When deemed appropriate, the Company discounts its liability for environmental matters. A weighted average risk free rate of 2% was used for the environmental liability at September 30, 2011. The book value of the liabilities will be accreted up to the undiscounted liability value through interest expense over the expected cash flow period. The accreted interest expense was less than $1 million for each of fiscal 2011, 2010 and 2009.

In June 2009, Cabot received an information request from the United States Environmental Protection Agency ("EPA") regarding Cabot's carbon black manufacturing facility in Pampa, Texas. The information request relates to the Pampa facility's compliance with certain regulatory and permitting requirements under the Clean Air Act, including the New Source Review ("NSR") construction permitting requirements. EPA has indicated that this information request is part of an EPA national initiative focused on the U.S. carbon black manufacturing sector. Cabot responded to EPA's information request in August 2009 and is in discussions with EPA. Based upon how EPA has handled similar NSR initiatives with other industrial sectors, it is anticipated that EPA will seek to require Cabot to employ additional technology control devices or approaches with respect to emissions at certain U.S. facilities and/or seek a civil penalty from Cabot. Should additional technology control devices be required, these costs would likely be capital in nature and would likely impact the Consolidated Statement of Operations over the depreciable lives of the associated assets.

Respirator Liabilities

Cabot has exposure in connection with a safety respiratory products business that a subsidiary acquired from American Optical Corporation ("AO") in an April 1990 asset purchase transaction. The subsidiary manufactured respirators under the AO brand and disposed of that business in July 1995. In connection with its acquisition of the business, the subsidiary agreed, in certain circumstances, to assume a portion of AO's liabilities, including costs of legal fees together with amounts paid in settlements and judgments, allocable to AO respiratory products used prior to the 1990 purchase by the Cabot subsidiary. In exchange for the subsidiary's assumption of certain of AO's respirator liabilities, AO agreed to provide to the subsidiary the benefits of: (i) AO's insurance coverage for the period prior to the 1990 acquisition and (ii) a former owner's indemnity of AO holding it harmless from any liability allocable to AO respiratory products used prior to May 1982.

Generally, these respirator liabilities involve claims for personal injury, including asbestosis, silicosis and coal worker's pneumoconiosis, allegedly resulting from the use of respirators that are claimed to have been negligently designed or labeled. Neither Cabot, nor its past or present subsidiaries, at any time manufactured asbestos or asbestos-containing products. Moreover, not every person with exposure to asbestos, silica or coal mine dust giving rise to a claim used a form of respiratory protection. At no time did this respiratory product line represent a significant portion of the respirator market. In addition, other parties, including AO, AO's insurers, and another former owner and its insurers (collectively, the "Payor Group"), are responsible for significant portions of the costs of these liabilities, leaving Cabot's subsidiary with a portion of the liability in only some of the pending cases.

The subsidiary transferred the business to Aearo Corporation ("Aearo") in July 1995. Cabot agreed to have the subsidiary retain certain liabilities allocable to respirators used prior to the 1995 transaction so long as Aearo paid, and continues to pay, Cabot an annual fee of $400,000. Aearo can discontinue payment of the fee at any time, in which case it will assume the responsibility for and indemnify Cabot against the liabilities allocable to respirators manufactured and used prior to the 1995 transaction. Cabot anticipates that it will continue to receive payment of the $400,000 fee from Aearo and thereby retain these liabilities for the foreseeable future. Cabot has no liability in connection with any products manufactured by Aearo after 1995.

As of September 30, 2011 and 2010, there were approximately 42,000 and 45,000 claimants, respectively, in pending cases asserting claims against AO in connection with respiratory products. Cabot has contributed to the Payor Group's defense and settlement costs with respect to a percentage of pending claims depending on several factors, including the period of alleged product use. In order to quantify Cabot's estimated share of liability for pending and future respirator liability claims, Cabot engaged, through counsel, the assistance of Hamilton, Rabinovitz & Alschuler, Inc. ("HR&A"), a leading consulting firm in the field of tort liability valuation. The methodology developed by HR&A addresses the complexities surrounding Cabot's potential liability by making assumptions about future claimants with respect to periods of asbestos, silica and coal mine dust exposure and respirator use. Using those and other assumptions, HR&A estimated the number of future asbestos, silica and coal mine dust claims that would be filed and the related costs that would be incurred in resolving both currently pending and future claims. On this basis, HR&A then estimated the net present value of the share of these liabilities that reflected Cabot's period of direct manufacture and Cabot's contractual obligations. Based on the HR&A estimates, Cabot has a reserve for these matters of $11 million on a net present value basis ($16 million on an undiscounted basis) at September 30, 2011.

Cabot's current estimate of the cost of its share of existing and future respirator liability claims is based on facts and circumstances existing at this time. Developments that could affect its estimate include, but are not limited to, (i) significant changes in the number of future claims, (ii) changes in the rate of dismissals without payment of pending silica and non-malignant asbestos claims, (iii) significant changes in the average cost of resolving claims, (iv) significant changes in the legal costs of defending these claims, (v) changes in the nature of claims received, (vi) changes in the law and procedure applicable to these claims, (vii) the financial viability of members of the Payor Group, (viii) a change in the availability of AO's insurance coverage or the indemnity provided by AO's former owner, (ix) changes in the allocation of costs among the Payor Group and (x) a determination that the Company's assumptions regarding the contractual obligations on which it has estimated its share of liability are inaccurate. Cabot cannot determine the impact of these potential developments on its current estimate of its share of liability for existing and future claims. Accordingly, the actual amount of these liabilities for existing and future claims could be different than the reserved amount.

The $11 million liability for respirator claims is recognized on a discounted basis using a discount rate of 5.3%, which represents management's best estimate of the risk free rate to apply to the cash flow payments of the liability that are projected through 2062. The total expected aggregate undiscounted amount of future payments is $16 million. Cabot estimates payments of approximately $2 million, $1 million, $1 million, $1 million, and $1 million in fiscal 2012, 2013, 2014, 2015 and 2016, respectively, and a total of $10 million in fiscal 2017 through 2062. The book value of the liabilities will be accreted up to the undiscounted liability value through interest expense over the expected cash flow period, which was less than $1 million in fiscal 2011. Cash payments were $5 million in fiscal 2011 and $2 million in each of 2010 and 2009 related to this liability. If the timing of Cabot's actual payments made for respirator claims differs significantly from the Company's estimated payment schedule, and the Company determines that it can no longer reasonably predict the timing of such payments, Cabot then could be required to record the reserve amount on an undiscounted basis on its Consolidated Balance Sheets, causing an immediate impact to earnings.

Other

During the fiscal year ended September 30, 2011, the Company recognized a benefit of approximately $9 million related to a legal judgment associated with a feedstock pipeline breakage that occurred in a prior period. This benefit was recorded within Cost of sales and Other expense in the Consolidated Statements of Operations.

The Company has various other lawsuits, claims and contingent liabilities arising in the ordinary course of its business and with respect to the Company's divested businesses. In the opinion of the Company, although final disposition of some or all of these other suits and claims may impact the Company's financial statements in a particular period, they are not expected in the aggregate to have a material adverse effect on the Company's financial position.

The entire disclosure for commitments and contingencies.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 14
-Paragraph 3
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 9, 10, 11, 12
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
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-Name Accounting Standards Codification
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Concentration Of Credit Risk

Concentration Of Credit Risk

12 Months Ended

Sep. 30, 2011

Concentration Of Credit Risk

Note U. Concentration of Credit Risk

Credit risk represents the loss that would be recognized if counterparties failed to completely perform as contracted. Financial instruments that subject Cabot to credit risk consist principally of cash and cash equivalents, investments, trade receivables and derivatives. Cabot maintains financial instruments with major banks and financial institutions. The Company has not experienced any material credit losses related to these instruments held at these financial institutions. Furthermore, concentrations of credit risk exist for groups of customers when they have similar economic characteristics that would cause their ability to meet contractual obligations to be similarly affected by changes in economic or other conditions.

No customer individually represented 10% or more of consolidated net sales for fiscal 2011. During fiscal 2010 and 2009, The Goodyear Tire and Rubber Company accounted for approximately 12% and 11%, respectively, of Cabot's annual consolidated net sales.

Tire manufacturers in the Rubber Blacks Business comprise a significant portion of Cabot's trade receivable balance. The accounts receivable balance for these significant customers are as follows:


	September 30
	2011		2010
	(Dollars in millions)
Tire manufacturers	$	318	$	259

Cabot has not experienced significant losses in the past from these customers. Cabot monitors its exposure to customers to manage potential credit losses.

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15A
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 94-6
-Paragraph 21, 22, 24
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Financial Information By Segment & Geographic Area

Financial Information By Segment & Geographic Area

12 Months Ended

Sep. 30, 2011

Financial Information By Segment & Geographic Area

Note V. Financial Information by Segment & Geographic Area

Segment Information

Cabot is organized into four business segments: the Core Segment, the Performance Segment, the New Business Segment and the Specialty Fluids Segment. During the fourth quarter of fiscal 2011, management made changes in its business organizational and financial reporting structure. First, the Cabot Elastomer Composites Business was reclassified from the Rubber Blacks Business in the Core Segment to the New Business Segment to enable the Business to have a stronger focus on the penetration of elastomer composite products in non-tire applications. Second, corporate business development costs related to new technology efforts in areas such as energy storage and discharge in battery applications, solar energy applications, and graphenes in composite materials were reclassified from the New Business Segment to Unallocated corporate costs. This change was made because these efforts support the entire Company. Finally, the effect on cost of sales from LIFO inventory assumptions, which was formerly allocated to the Segments, is now an unallocated expense and included in the line entitled General unallocated (expense) income in the financial information by segment table below to ensure better clarity of fundamental business profitability. In addition, during the fourth quarter of fiscal 2011, Cabot entered into an agreement to sell its Supermetals Business. As a result, the results of operations for the Supermetals Business are now reported as a discontinued operation, and overhead costs that had previously been allocated to the Business have been allocated to the remaining Segments.

While the Chief Operating Decision Maker uses a number of performance measures to manage the performance of the segments and allocate resources to them, segment operating profit (loss) before interest and taxes ("Segment EBIT") is the measure that is most consistently used and is, therefore, the measure presented for each segment in the financial information by segment table below on the line entitled Income (loss) before taxes. Segment EBIT excludes certain items, meaning items considered by management to be unusual and not representative of segment results. In addition, Segment EBIT includes Equity in net income of affiliated companies, net of tax, royalties paid by equity affiliates and Net income attributable to noncontrolling interests, net of tax, but exclude Interest expense, foreign currency transaction gains and losses, interest income, dividend income, unearned revenue, the effects of LIFO accounting for inventory as stated above, and unallocated general and corporate costs. Segment assets exclude cash, short-term investments, cost investments, income taxes receivable, deferred taxes and headquarters' assets, which are included in unallocated and other. Expenditures for additions to long-lived assets include total equity and other investments (including available-for-sale securities), property, plant and equipment, intangible assets and assets held for rent.

Core Segment

Rubber Blacks products are used in tires and industrial products. Rubber blacks have traditionally been used in the tire industry as a rubber reinforcing agent and are also used as a performance additive. In industrial products such as hoses, belts, extruded profiles and molded goods, rubber blacks are used to improve the physical performance of the product.

Performance Segment

The Performance Segment is comprised of two product lines: specialty grades of carbon black and masterbatch products (referred to together as "Performance Products"); and fumed silica, fumed alumina and dispersions thereof (referred to together as "Fumed Metal Oxides"). The net sales from each of these businesses for fiscal 2011, 2010 and 2009 are as follows:


	Years Ended September 30
	2011		2010		2009
	(Dollars in millions)
Performance Products Business	$	626	$	531	$	410
Fumed Metal Oxides Business		254		252		210

Total Performance Segment	$	880	$	783	$	620

In each product line, the business designs, manufactures and sells materials that deliver performance in a broad range of customer applications across the automotive, construction and infrastructure, and electronics and consumer products sectors.

Cabot's specialty grades of carbon black are used to impart color, provide rheology control, enhance conductivity and static charge control, provide UV protection, enhance mechanical properties, and provide chemical flexibility through surface treatment. These products are used in a wide variety of applications, such as inks, coatings, cables, pipes, toners and electronics. In addition, Cabot manufactures and sources masterbatch products and compounds that are marketed to the plastics industry.

Fumed silica is an ultra-fine, high-purity particle used as a reinforcing, thickening, abrasive, thixotropic, suspending or anti-caking agent in a wide variety of products produced for the automotive, construction, microelectronics, and consumer products industries. These products include adhesives, sealants, cosmetics, inks, toners, silicone rubber, coatings, polishing slurries and pharmaceuticals. Fumed alumina, also an ultra-fine, high-purity particle, is used as an abrasive, absorbent or barrier agent in a variety of products, such as inkjet media, lighting, coatings, cosmetics and polishing slurries.

New Business Segment

The New Business Segment is comprised of the Inkjet Colorants, Aerogel, Cabot Superior MicroPowders ("CSMP"), and Cabot Elastomer Composites ("CEC") Businesses. The net sales from each of these Businesses are as follows:


	Years Ended September 30
	2011		2010		2009
	(Dollars in millions)
Inkjet Colorants Business	$	65	$	57	$	46
Aerogel Business		24		24		15
Cabot Superior MicroPowders Business		11		7		4
Cabot Elastomer Composites Business		17		17		5

Total New Business Segment	$	117	$	105	$	70

The Inkjet Colorants Business produces and sells aqueous inkjet colorants primarily to the inkjet printing market. The Company's inkjet colorants are high-quality pigment-based black and other colorant dispersions manufactured by surface treating specialty grades of carbon black and other pigments. The dispersions are used in aqueous inkjet inks to impart color (optical density or chroma) with improved durability (waterfastness, lightfastness and rub resistance) while maintaining high printhead reliability. Cabot's inkjet colorants are produced for various inkjet printing applications including small office and home office, corporate office, and commercial and industrial printing, as well as for other niche applications that require a high level of dispersibility and colloidal stability.

Cabot's aerogel is a hydrophobic, silica-based particle with a high surface area that is used in a variety of thermal insulation and specialty chemical applications. In the construction industry, the product is used in insulative composite building products and translucent skylight, window, wall and roof systems for insulating eco-daylighting applications. In the oil and gas industry, aerogel is used to insulate subsea pipelines. In the specialty chemicals industry, the product is used to provide matte finishing, insulating and thickening properties for use in a variety of applications. The Company continues to focus on application and market development activities for use of aerogel in these and other new applications.

The principal area of commercial focus for CSMP is in developing covert taggants for a broad range of anti-counterfeiting security applications, including brand security, currency, tax stamps, identification and fuel markers. Covert taggants are invisible, unique markers that are added to products to determine their authenticity through the use of custom detectors or readers. The Company's taggants are manufactured using a proprietary process, which produces highly uniform materials with unique signatures.

In addition to the carbon black the Company makes using conventional carbon black manufacturing methods, it has developed elastomer composite products that are compounds of natural latex rubber and carbon black made by a patented liquid phase process. The Company believes that these compounds improve abrasion/wear resistance, reduce fatigue and reduce rolling resistance compared to natural rubber/carbon black compounds made by conventional methods. The Company's CEC products are targeted for tire, defense, mining, automotive, and aerospace applications.

Specialty Fluids Segment

The Specialty Fluids Segment produces and markets cesium formate as a drilling and completion fluid for use primarily in high pressure and high temperature oil and gas well construction. Cesium formate products are solids-free, high-density fluids that have a low viscosity, enabling safe and efficient well construction and workover operations. The fluid is resistant to high temperatures, minimizes damage to producing reservoirs and is readily biodegradable in accordance with testing guidelines set by the Organization for Economic Cooperation and Development. In a majority of applications, cesium formate is blended with other formates or products.

Financial information by segment is as follows:


	Core Segment		Performance Segment		New Business Segment			Specialty Fluids Segment		Segment Total		Unallocated and Other^{(1), (3)}			Consolidated Total
	(Dollars in millions)
Years Ended September 30
2011
Revenues from external customers⁽²⁾		1,952		880		117			69		3,018		84			3,102
Depreciation and amortization		80		37		11			3		131		8			139
Equity in earnings of affiliated companies		7		1		—			—		8		—			8
Income (loss) from continuing operations before taxes⁽³⁾		183		140		9			22		354		(151	)		203
Assets⁽⁴⁾		1,509		661		90			101		2,361		780			3,141
Investment in equity-based affiliates		50		10		—			—		60		—			60
Total expenditures for additions to long-lived assets⁽⁵⁾		126		99		7			3		235		6			241
2010
Revenues from external customers⁽²⁾		1,660		783		105			81		2,629		87			2,716
Depreciation and amortization		74		35		10			2		121		16			137
Equity in earnings of affiliated companies		6		1		—			—		7		—			7
Income (loss) from continuing operations before taxes⁽³⁾		139		125		15			35		314		(148	)		166
Assets⁽⁴⁾		1,277		544		93			95		2,009		877			2,886
Investment in equity-based affiliates		51		10		—			—		61		—			61
Total expenditures for additions to long-lived assets⁽⁵⁾		62		38		3			1		104		3			107
2009
Revenues from external customers⁽²⁾		1,283		620		70			64		2,037		71			2,108
Depreciation and amortization		99		46		11			2		158		6			164
Equity in earnings of affiliated companies		5		—		—			—		5		—			5
Income (loss) from continuing operations before taxes⁽³⁾		21		25		(3	)		18		61		(160	)		(99	)
Assets⁽⁴⁾		1,215		507		93			78		1,893		783			2,676
Investment in equity-based affiliates		56		4		—			—		60		—			60
Total expenditures for additions to long-lived assets⁽⁵⁾		72		32		4			1		109		1			110

⁽¹⁾

Unallocated and other includes certain items and eliminations that are not allocated to the operating segments. Management does not consider these items necessary for an understanding of the operating results of these segments and such amounts are excluded in the segment reporting to the Chief Operating Decision Maker.

⁽²⁾	Unallocated and other reflects royalties paid by equity affiliates, external shipping and handling fees, and the impact of the corporate adjustment for unearned revenue.


	Years Ended September 30
	2011			2010		2009
	(Dollars in millions)
Royalties received from equity affiliates and other operating revenues	$	(2	)	$	7	$	6
Shipping and handling fees		86			80		65

Total	$	84		$	87	$	71

⁽ ³ ⁾

Income (loss) from continuing operations before taxes for Unallocated and Other includes:


	Years Ended September 30
	2011			2010			2009
	(Dollars in millions)
Interest expense	$	(39	)	$	(40	)	$	(30	)
Certain items^(a)		(19	)		(53	)		(92	)
Equity in net income of affiliated companies^(b)		(8	)		(7	)		(5	)
Unallocated corporate costs^(c)		(53	)		(48	)		(36	)
General unallocated (expense) income^(d)		(32	)		—			3

Total	$	(151	)	$	(148	)	$	(160	)

^(a)

Certain items are items that management does not consider to be representative of segment results and they are, therefore, excluded from segment EBIT. Certain items for fiscal 2011 primarily include charges for global restructuring activities discussed in Note P. Certain items for fiscal 2010 include $46 million related to global restructuring activities, $3 million for environmental reserves and legal settlements, $2 million long-lived asset impairment of land related to a former carbon black site, and a $2 million addition in the reserve for respirator claims. For fiscal 2009, certain items include charges of $87 million for the Company's global restructuring activities, $4 million for executive transition costs, and $1 million for the write-down of impaired investments.

^(b)

Equity in net income of affiliated companies is included in segment EBIT and is removed from Unallocated and other to reconcile to income (loss) from operations before taxes.

^(c)

Unallocated corporate costs are not controlled by the segments and primarily benefit corporate interests.

^(d)

General unallocated (expense) income consists of gains (losses) arising from foreign currency transactions, net of other foreign currency risk management activities, the impact of accounting for certain inventory on a LIFO basis, and the profit or loss related to the corporate adjustment for unearned revenue. Additionally, for fiscal 2011, this amount included a $3 million charge related to a change in the net worth tax regulations in Colombia, and $3 million related to a portion of the benefit from a legal judgment.

⁽⁴⁾	Unallocated and Other assets includes cash, marketable securities, cost investments, income taxes receivable, deferred taxes, headquarters' assets, and Current and Non-current assets held for sale.

⁽⁵⁾	Expenditures for additions to long-lived assets include total equity and other investments, property, plant and equipment, intangible assets and assets held for rent.

Geographic Information

Sales are attributed to the United States and to all foreign countries based on the location from which the sale originated. Revenues from external customers and long-lived assets attributable to an individual country, other than the United States and China, were not material for disclosure.

Revenues from external customers and long-lived asset information by geographic area are summarized as follows:


	United States		China		Other Foreign Countries		Consolidated Total
	(Dollars in millions)
Years Ended September 30,
2011
Revenues from external customers	$	589	$	554	$	1,959	$	3,102
Long-lived assets⁽¹⁾	$	240	$	280	$	650	$	1,170

2010
Revenues from external customers	$	546	$	458	$	1,712	$	2,716
Long-lived assets⁽¹⁾	$	233	$	210	$	640	$	1,083

2009
Revenues from external customers	$	332	$	281	$	1,495	$	2,108
Long-lived assets⁽¹⁾	$	320	$	201	$	593	$	1,114

⁽¹⁾	Long-lived assets include total equity and other investments, net property, plant and equipment, net intangible assets and assets held for rent.

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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-Publisher FASB
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-Number 131
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Unaudited Quarterly Financial Information

Unaudited Quarterly Financial Information

12 Months Ended

Sep. 30, 2011

Unaudited Quarterly Financial Information

Note W. Unaudited Quarterly Financial Information

Unaudited financial results by quarter for fiscal 2011 and 2010 are summarized below.


	Quarter Ended
	December			March			June			September			Year
	(Dollars in millions, except per share amounts and ratios)
Fiscal 2011
Consolidated Net Income
Net sales and other operating revenues	$	694		$	739		$	836		$	833		$	3,102

Gross profit		131			134			152			141			558
Selling and administrative expenses		63			62			61			63			249
Research and technical expenses		15			18			16			17			66

Income from operations		53			54			75			61			243
Net interest expense and other charges		(7	)		(6	)		(13	)		(14	)		(40	)

Income from continuing operations before taxes		46			48			62			47			203
Benefit (provision) for income taxes		15			(9	)		(10	)		(2	)		(6	)
Equity in earnings of affiliated companies		3			1			2			2			8
Income from discontinued operations, net of tax		16			16			13			8			53

Net income		80			56			67			55			258
Net income attributable to noncontrolling interests, net of tax		5			5			7			5			22

Net income attributable to Cabot Corporation	$	75		$	51		$	60		$	50		$	236

Income per share - diluted:
Income from continuing operations	$	0.88		$	0.52		$	0.73		$	0.64		$	2.77
Income from discontinued operations		0.25			0.24			0.19			0.12			0.80

Net income attributable to Cabot Corporation	$	1.13		$	0.76		$	0.92		$	0.76		$	3.57


	Quarter Ended
	December			March			June			September			Year
	(Dollars in millions, except per share amounts and ratios)
Fiscal 2010
Consolidated Net Income
Net sales and other operating revenues	$	634		$	676		$	706		$	700		$	2,716

Gross profit		126			131			136			117			510
Selling and administrative expenses		67			58			62			54			241
Research and technical expenses		17			18			14			16			65

Income from operations		42			55			60			47			204
Net interest expense and other charges		(9	)		(15	)		(6	)		(8	)		(38	)

Income from continuing operations before taxes		33			40			54			39			166
Benefit (provision) for income taxes		(8	)		3			(14	)		(11	)		(30	)
Equity in earnings of affiliated companies		3			1			1			2			7
Income from discontinued operations, net of tax		6			3			10			7			26

Net income		34			47			51			37			169
Net income attributable to noncontrolling interests, net of tax		5			4			4			2			15

Net income attributable to Cabot Corporation	$	29		$	43		$	47		$	35		$	154

Income per share - diluted:
Income from continuing operations	$	0.36		$	0.59		$	0.57		$	0.42		$	1.94
Income from discontinued operations		0.08			0.06			0.15			0.12			0.41

Net income attributable to Cabot Corporation	$	0.44		$	0.65		$	0.72		$	0.54		$	2.35

The entire disclosure for the quarterly financial data in the annual financial statements. The disclosure may include a tabular presentation of financial information for each fiscal quarter for the current and previous year, including revenues, gross profit, income or loss before extraordinary items and earnings per share data. It also includes an indication if the information in the note is unaudited, comments on the aggregate effect of year-end adjustments, and an explanation of matters or transactions that affect comparability or are pertinent to an understanding of the information furnished.

Principles Of Consolidation

Significant Accounting Policies (Policy)

12 Months Ended

Sep. 30, 2011

Significant Accounting Policies

Principles of Consolidation

Cash And Cash Equivalents

Cash and Cash Equivalents

Inventories

Inventories

Investments

Investments

Property, Plant And Equipment

Property, Plant and Equipment

Goodwill And Other Intangible Assets

Goodwill and Other Intangible Assets

Assets Held For Rent

Assets Held for Rent

Assets Held For Sale

Assets Held for Sale

Assets and liabilities held for sale in the Consolidated Balance Sheets pertain to applicable assets and liabilities of the Supermetals business. See Note C for additional information.

Asset Retirement Obligations

Asset Retirement Obligations

Impairment Of Long-Lived Assets

Impairment of Long-Lived Assets

Foreign Currency Translation

Foreign Currency Translation

Financial Instruments

Financial Instruments

Revenue Recognition

Revenue Recognition

Shipping and handling charges related to sales transactions are recorded as revenue when billed to customers or included in the sales price. Shipping and handling costs are included in cost of sales.

The following table shows the relative size of the revenue recognized in each of the Company's reportable segments:


	Years ended September 30
	2011			2010			2009
Core Segment		65	%		63	%		63	%
Performance Segment		29	%		30	%		31	%
New Business Segment		4	%		4	%		3	%
Specialty Fluids Segment		2	%		3	%		3	%

Accounts and Notes Receivable

Accounts and Notes Receivable

Stock-Based Compensation

Stock-based Compensation

Research And Technical Expenses

Research and Technical Expenses

Research and technical expenses include salaries, equipment and material expenditures, and contractor fees and are expensed as incurred.

Income Taxes

Income Taxes

Accumulated Other Comprehensive Income

Accumulated Other Comprehensive Income

Environmental Costs

Environmental Costs

Use Of Estimates

Use of Estimates

Significant Accounting Policies (Tables)

12 Months Ended

Sep. 30, 2011

Significant Accounting Policies

Segment Reporting Revenue Percentage


	Years ended September 30
	2011			2010			2009
Core Segment		65	%		63	%		63	%
Performance Segment		29	%		30	%		31	%
New Business Segment		4	%		4	%		3	%
Specialty Fluids Segment		2	%		3	%		3	%

Discontinued Operations (Tables)

12 Months Ended

Sep. 30, 2011

Income (Loss) From Discontinued Operations, Net Of Tax [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Components Of Discontinued Operations


	Years Ended September 30
	2011			2010			2009
	(Dollars in millions)
Net sales and other operating revenues	$	201		$	177		$	135

Income (loss) from operations before income taxes		84			42			(3	)
(Provision) benefit for income taxes		(31	)		(16	)		1

Income (loss) from discontinued operations, net of tax	$	53		$	26		$	(2	)

Assets Held For Sale And Liabilities Associated With Assets Held For Sale [Member]

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Components Of Discontinued Operations


	September 30,
	2011		2010
	(Dollars in millions)
Assets
Accounts and notes receivable, net of reserve for doubtful accounts	$	41	$	36
Inventories		64		66
Prepaid expenses and other current assets		1		1

Total current assets held for sale	$	106	$	103

Net property, plant and equipment	$	39	$	38
Other assets		—		2

Total noncurrent assets held for sale	$	39	$	40

Liabilities
Accounts payable and accrued liabilities	$	12	$	16

Total current liabilities held for sale	$	12	$	16

Other liabilities	$	6	$	6

Total noncurrent liabilities held for sale	$	6	$	6

Tabular disclosure of disposal groups, which may include the gain (loss) recognized in the income statement and the income statement caption that includes that gain (loss), amounts of revenues and pretax profit or loss reported in discontinued operations, the classification and carrying value of the assets and liabilities comprising the disposal group, and the segment in which the disposal group was reported. Also may include the amount of adjustments to amounts previously reported in discontinued operations such as resolution of contingencies arising from the disposal transaction or the operations of the component prior to disposal.

Components Of The Company's Inventories

Inventories (Tables)

12 Months Ended

Sep. 30, 2011

Inventories


	September 30
	2011		2010
	(Dollars in millions)
Raw materials	$	120	$	94
Work in process		3		3
Finished goods		233		179
Other		37		31

Total	$	393	$	307

Investments (Tables)

12 Months Ended

Sep. 30, 2011

Investments

Equity Method Investments Of Income Statement And Balance Sheet Information


	September 30
	2011		2010		2009
	(Dollars in millions)
Condensed Income Statement Information:
Net sales	$	312	$	363	$	172
Gross profit		55		50		33
Net income		18		20		10
Condensed Balance Sheet Information:
Current assets	$	109	$	141	$	87
Non-current assets		55		73		64
Current liabilities		38		32		34
Non-current liabilities		3		50		7
Net assets		123		132		110

Property, Plant And Equipment (Tables)

12 Months Ended

Sep. 30, 2011

Property, Plant And Equipment

Components Of Property, Plant And Equipment


	September 30
	2011			2010
	(Dollars in millions)
Land and land improvements	$	73		$	69
Buildings		479			475
Machinery and equipment		2,076			2,011
Other		162			221
Construction in progress		177			102

Total property, plant and equipment		2,967			2,878
Less: accumulated depreciation		(1,931	)		(1,941	)

Net property, plant and equipment	$	1,036		$	937

Goodwill And Other Intangible Assets (Tables)

12 Months Ended

Sep. 30, 2011

Goodwill And Other Intangible Assets

Schedule Of Goodwill Balances


	Rubber Blacks		Fumed Metal Oxides		Security Materials		Total
	(Dollars in millions)
Balance at September 30, 2009	$	26	$	11	$	—	$	37
Goodwill acquired⁽¹⁾		—		—		1		1
Foreign currency translation adjustment		1		—		—		1

Balance at September 30, 2010		27		11		1		39
Foreign currency translation adjustment and other		—		—		1		1

Balance at September 30, 2011	$	27	$	11	$	2	$	40

⁽¹⁾	Goodwill acquired relates to the acquisition of Oxonica Materials Inc. in Security Materials.

Schedule Of Finite-Lived Intangible Assets


	Years Ended September 30
	2011							2010
	Gross Carrying Value		Accumulated Amortization			Net Intangible Assets		Gross Carrying Value		Accumulated Amortization			Net Intangible Assets
	(Dollars in millions)
Patents	$	2	$	(2	)	$	—	$	2	$	(2	)	$	—
Other intangible assets assets⁽¹⁾		3		—			3		3		—			3

Total intangible assets	$	5	$	(2	)	$	3	$	5	$	(2	)	$	3

⁽¹⁾	Other intangible assets relates to the acquisition of Oxonica Materials Inc. in Security Materials in fiscal 2010.

Tabular disclosure of goodwill by reportable segment and in total. Disclosure details may include, but are not limited to, the carrying amount of goodwill, goodwill acquired during the year, goodwill impairment losses recognized, goodwill written-off due to the sale of a business unit, goodwill not yet allocated, and any other changes to goodwill.

Accounts Payable, Accrued Liabilities And Other Liabilities

Accounts Payable, Accrued Liabilities And Other Liabilities (Tables)

12 Months Ended

Sep. 30, 2011

Components Of Accounts Payable And Accrued Liabilities


	September 30
	2011		2010
	(Dollars in millions)
Accounts payable	$	330	$	292
Accrued employee compensation		44		58
Accrued severance and restructuring		11		21
Other accrued liabilities		76		60

Total	$	461	$	431

Components Of Other Long-Term Liabilities


	September 30
	2011		2010
	(Dollars in millions)
Employee benefit plan liabilities	$	161	$	160
Non-current tax liabilities		50		63
Financial instrument liabilities		39		39
Other accrued liabilities		49		56

Total	$	299	$	318

Debt And Other Obligations (Tables)

12 Months Ended

Sep. 30, 2011

Debt And Other Obligations

Schedule Of Long-Term Obligations


	September 30
	2011			2010
	(Dollars in millions)
Variable Rate Debt:
$550 million Revolving Credit Facility, expires 2016	$	—		$	—
Chinese Renminbi Notes, due through 2012, 5.40%		15			16

Total variable rate debt		15			16
Fixed Rate Debt:
5% Notes due 2016	$	300		$	300
Medium Term Notes:
Notes due 2011, 7.26%	$	—		$	15
Notes due 2012, 7.70%—8.28%		30			30
Note due 2018, 7.42%		30			30
Notes due 2022, 8.346%—8.47%		15			15
Note due 2027, 6.57%—7.28%		8			8

Total Medium Term Notes		83			98
Eurobond, due 2013, 5.25%		178			179
ESOP Note, due 2013, 8.29%		14			20
Chinese Renminbi Notes, due 2012, 6.10%		5			4
Other, due 2027, 2%		5			5

Total fixed rate debt		585			606
Capital lease obligations, due through 2031		15			3
Unamortized debt discount		(2	)		(2	)

Total debt		613			623
Less current portion of long-term debt		(57	)		(23	)

Total long-term debt	$	556		$	600

Schedule Of Future Years Payment


Fiscal Years Ended	Principal payments on long term debt⁽¹⁾		Payments on Capital Lease Obligations		Total
	(Dollars in millions)
2012	$	56	$	1	$	57
2013		182		1		183
2014		2		1		3
2015		—		1		1
2016		300		1		301
Thereafter		57		10		67

Total	$	597	$	15	$	612

⁽¹⁾	Payment of long-term debt excludes settlements of cross currency swaps.

Fair Value Measurements (Tables)

12 Months Ended

Sep. 30, 2011

Fair Value Measurements

Schedule Of Fair Value Of Derivatives, Net Of Legal Right To Offset Derivative Settlements


	September 30
	2011		2010
	Level 2 Inputs		Level 2 Inputs
	(Dollars in Millions)
Assets at fair value:
Guaranteed investment contract⁽¹⁾	$	14	$	14
Derivatives relating to interest rates⁽²⁾		3		5

Total assets at fair value	$	17	$	19

Liabilities at fair value:
Derivatives relating to foreign currency⁽²⁾	$	41	$	42
Hedged long-term debt		61		77

Total liabilities at fair value	$	102	$	119

⁽¹⁾	Included in "Other assets" in the Consolidated Balance Sheets.

⁽²⁾	Included in "Prepaid expenses and other current assets", "Other assets", "Accounts payable and accrued liabilities" and "Other liabilities" in the Consolidated Balance Sheets.

Fair Value Of Financial Instruments (Tables)

12 Months Ended

Sep. 30, 2011

Fair Value Of Financial Instruments

Carrying Amounts And Fair Values Of Company's Financial Instruments


	2011				2010
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
	(Dollars in millions)
Assets:
Cash and cash equivalents	$	286	$	286	$	387	$	387
Accounts and notes receivable		659		659		540		540
Derivative instruments		1		1		2		2
Liabilities:
Notes payable to banks		86		86		29		29
Accounts payable and accrued liabilities		461		461		431		431
Long-term debt—fixed rate		585		633		604		661
Long-term debt—floating rate		15		15		16		16
Capital lease obligations		15		15		3		3
Derivative instruments		39		39		39		39

Financial Instruments (Tables)

12 Months Ended

Sep. 30, 2011

Schedule Of Derivative Instruments In Statement Of Financial Position, Fair Value


Fair Value of Derivative Instruments	Consolidated Balance Sheet Caption	September 30, 2011		September 30, 2010
		(Dollars in millions)
Asset Derivatives
Derivatives designated as hedges Interest rate⁽¹⁾	Prepaid expenses and other current assets and Other liabilities	$	3	$	5

Total derivatives designated as hedges		$	3	$	5

Derivatives not designated as hedges Foreign currency	Prepaid expenses and other current assets	$	1	$	—
Commodity contracts⁽²⁾	Prepaid expenses and other current assets, and Other assets		1		2

Total derivatives not designated as hedges		$	2	$	2

Total Asset Derivatives		$	5	$	7

Liability Derivatives
Derivatives designated as hedges Foreign currency	Accounts payable and accrued liabilities	$	1	$	—

Total derivatives designated as hedges		$	1	$	—

Derivatives not designated as hedges Foreign currency⁽¹⁾	Accounts payable and accrued liabilities, and Other liabilities	$	41	$	42
Commodity contracts⁽²⁾	Prepaid expenses and other current assets, and Other assets		1		2

Total derivatives not designated as hedges		$	42	$	44

Total Liability Derivatives		$	43	$	44

⁽¹⁾

⁽²⁾	Contracts in an asset and liability position presented on a gross basis in this table have the legal right of offset and, therefore, are presented on a net basis in "Prepaid expenses and other current assets" and noncurrent "Other assets" in the consolidated balance sheet.

Interest Rate Risk Management [Member]

Schedule Of Derivatives Held To Manage Risk


		Notional Amount
Description	Borrowing	September 30, 2011	September 30, 2010	Hedge Designation
Interest Rate Swap—Fixed to Variable	Eurobond (20% of $175 million)	USD 35 million	USD 35 million	Fair Value
Interest Rate Swap—Fixed to Variable⁽¹⁾	Medium Term Notes	—	USD 15 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 8 million	USD 8 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 5 million	USD 5 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 5 million	USD 5 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 5 million	USD 5 million	Fair Value

⁽¹⁾	Cabot's interest rate swap derivative instrument and the hedged debt borrowing matured during fiscal 2011.

Foreign Currency Risk Management [Member]

Schedule Of Derivatives Held To Manage Risk


Description	Borrowing	Notional Amount		Hedge Designation
Description	Borrowing	September 30, 2011	September 30, 2010	Hedge Designation
Cross Currency Swap	Eurobond (80% of $175 million)	USD 140 million swapped to EUR 124 million	USD 140 million swapped to EUR 124 million	No designation

Cross Currency Swap	Eurobond (20% of $175 million)	USD 35 million swapped to EUR 31 million	USD 35 million swapped to EUR 31 million	No designation

Forward Foreign Currency Contracts ⁽¹⁾	N/A	USD 54 million	USD 23 million	No designation

Forward Foreign Currency Contracts ⁽²⁾	N/A	JPY 12 million	—	Cash Flow

⁽¹⁾	Cabot's forward foreign exchange contracts are denominated primarily in the Australian dollar, British pound sterling, Canadian dollar, Euro, and Japanese yen.

⁽²⁾	Cabot's forward foreign exchange contracts designated as cash flow hedges were entered into during fiscal 2011.

Commodity Risk Management [Member]

Schedule Of Derivatives Held To Manage Risk


		Notional Amount
Description	Net Buyer / Net Seller	September 30, 2011	September 30, 2010	Hedge Designation
CERs	Buyer	EUR 1 million	EUR 2 million	No designation
EUAs	Seller	EUR 1 million	EUR 2 million	No designation

The entire disclosure for the entity's entire derivative instruments and hedging activities. Describes an entity's risk management strategies, derivatives in hedging activities and non-hedging derivative instruments, the assets, obligations, liabilities, revenues and expenses arising therefrom, and the amounts of and methodologies and assumptions used in determining the amounts of such items.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Change In Benefit Obligations And Change In Plan Assets

Employee Benefit Plans (Tables)

12 Months Ended

Sep. 30, 2011

Employee Benefit Plans


	Years Ended September 30
	2011						2010						2011						2010
	Pension Benefits												Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign			U.S.			Foreign
	(Dollars in millions)
Change in Benefit Obligations:
Benefit obligation at beginning of year	$	143		$	241		$	137		$	228		$	69		$	15		$	69		$	15
Service cost		5			6			5			5			1			—			1			—
Interest cost		6			11			7			10			2			1			3			1
Plan participants' contribution		—			1			—			1			—			—			—			—
Foreign currency exchange rate changes		—			1			—			(2	)		—			—			—			—
Loss (gain) from changes in actuarial assumptions		2			(9	)		6			19			(1	)		(1	)		3			—
Benefits paid ⁽¹⁾		(9	)		(16	)		(12	)		(20	)		(5	)		—			(6	)		—
Plan amendments		—			—			—			—			(2	)		—			(1	)		—
Settlements or curtailment gain		—			(1	)		—			—			—			—			—			(1	)
Other		—			2			—			—			—			—			—			—

Benefit obligation at end of year	$	147		$	236		$	143		$	241		$	64		$	15		$	69		$	15


	Years Ended September 30
	2011						2010						2011						2010
	Pension Benefits												Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign			U.S.			Foreign
	(Dollars in millions)
Change in Plan Assets:
Fair value of plan assets at beginning of year	$	104		$	197		$	104		$	193		$	—		$	—		$	—		$	—
Actual return on plan assets		8			2			10			16			—			—			—			—
Employer contribution		—			13			2			9			5			—			6			—
Plan participants' contribution		—			1			—			1			—			—			—			—
Foreign currency exchange rate changes		—			—			—			(2	)		—			—			—			—
Benefits paid⁽¹⁾		(9	)		(16	)		(12	)		(20	)		(5	)		—			(6	)		—

Fair value of plan assets at end of year	$	103		$	197		$	104		$	197		$	—		$	—		$	—		$	—

Funded status	$	(44	)	$	(39	)	$	(39	)	$	(44	)	$	(64	)	$	(15	)	$	(69	)	$	(15	)

Recognized liability⁽²⁾	$	(44	)	$	(39	)	$	(39	)	$	(44	)	$	(64	)	$	(15	)	$	(69	)	$	(15	)

⁽¹⁾	Included in this amount is $2 million and $1 million that the Company paid directly to the participants in its defined benefit plans in fiscal 2011 and 2010, respectively.

⁽²⁾	Included in this amount is $4 million of net pension liability as of September 30, 2011 and 2010 related to the Supermetals Business presented as Noncurrent Liabilities Held For Sale in the Consolidated Balance Sheets.

Assumptions Used To Determine Benefit Obligations

	Assumptions as of September 30
	2011						2010						2009
	Pension Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign
Actuarial assumptions as of the year-end measurement date:
Discount rate		4.5	%		4.8	%		4.5	%		4.4	%		5.3	%		5.0	%
Rate of increase in compensation		3.8	%		3.1	%		3.8	%		3.3	%		3.8	%		3.4	%
Actuarial assumptions used to determine net periodic benefit cost during the year:
Discount rate		4.5	%		4.3	%		5.3	%		5.0	%		7.5	%		6.4	%
Expected long-term rate of return on plan assets		7.8	%		6.1	%		7.8	%		6.1	%		7.8	%		6.5	%
Rate of increase in compensation		3.8	%		3.3	%		3.8	%		3.4	%		4.5	%		3.8	%


	Assumptions as of September 30
	2011						2010						2009
	Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign
Actuarial assumptions as of the year-end measurement date:
Discount rate		4.5	%		4.9	%		4.5	%		4.8	%		5.3	%		5.2	%
Initial health care cost trend rate		8.5	%		8.0	%		7.5	%		8.0	%		8.0	%		9.0	%
Actuarial assumptions used to determine net cost during the year:
Discount rate		4.5	%		4.8	%		5.3	%		5.2	%		7.5	%		7.1	%
Initial health care cost trend rate		7.5	%		8.0	%		8.0	%		9.0	%		8.0	%		9.0	%

Net Amounts Recognized In The Consolidated Balance Sheets


	Years Ended September 30
	2011						2010						2011						2010
	Pension Benefits												Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign			U.S.			Foreign
	(Dollars in millions)
Net Amounts Recognized in the Consolidated Balance Sheets
Noncurrent assets	$	—		$	10		$	—		$	5		$	—		$	—		$	—		$	—
Current liabilities		—			(1	)		(1	)		(1	)		(6	)		—			(6	)		—
Noncurrent liabilities		(44	)		(48	)		(38	)		(48	)		(58	)		(15	)		(63	)		(15	)

Amounts Recognized In Accumulated Other Comprehensive Income (Loss)


	Years Ended September 30
	2011				2010				2011					2010
	Pension Benefits								Postretirement Benefits
	U.S.		Foreign		U.S.		Foreign		U.S.			Foreign		U.S.			Foreign
	(Dollars in millions)
Net actuarial loss	$	34	$	52	$	32	$	54	$	2		$	2	$	3		$	3
Net prior service cost (credit)		1		—		1		—		(14	)		—		(16	)		—

Balance in accumulated other comprehensive income, pretax	$	35	$	52	$	33	$	54	$	(12	)	$	2	$	(13	)	$	3

Estimated Future Benefit Payments


	Pension Benefits				Postretirement Benefits
	U.S.		Foreign		U.S.		Foreign
	(Dollars in millions)
Years Ended:
2012	$	11	$	12	$	6	$	1
2013		10		17		6		—
2014		11		13		6		—
2015		11		13		6		—
2016		11		15		5		1
2017-2021		65		83		25		5

Net Periodic Defined Benefit Pension And Other Postretirement Benefit Costs


	Years Ended September 30
	2011						2010						2009						2011					2010					2009
	Pension Benefits																		Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign			U.S.			Foreign		U.S.			Foreign		U.S.			Foreign
	(Dollars in millions)
Service cost	$	5		$	6		$	5		$	5		$	4		$	5			1		$	—	$	1		$	—	$	2		$	—
Interest cost		6			11			7			11			8			12			2			1		3			1		5			1
Expected return on plan assets		(8	)		(13	)		(9	)		(11	)		(9	)		(12	)		—			—		—			—		—			—
Amortization of prior service cost (credit)		—			—			—			—			—			—			(3	)		—		(4	)		—		(1	)		—
Net losses (gains)		—			3			—			2			(1	)		1			—			—		—			—		—			—
Settlements or curtailments cost (income)		—			—			—			1			—			(1	)		—			—		—			—		(1	)		—
Other		—			2			—			—			—			—			—			—		—			—		—			—

Net periodic benefit cost	$	3		$	9		$	3		$	8		$	2		$	5		$	—		$	1	$	—		$	1	$	5		$	1

Other Changes In Plan Assets And Benefit Obligations Recognized In Other Comprehensive Income


	Years Ended September 30
	2011					2010					2009					2011						2010				2009
	Pension Benefits															Postretirement Benefits
	U.S.		Foreign			U.S.		Foreign			U.S.		Foreign			U.S.			Foreign			U.S.		Foreign		U.S.			Foreign
	(Dollars in millions)
Net losses (gains)	$	2	$	1		$	5	$	12		$	34	$	18			(1	)	$	(1	)	$	1	$	—	$	11		$	2
Prior service cost		—		—			—		—			—		1			(2	)		—			—		—		(17	)		—
Amortization of prior service (cost) credit		—		—			—		—			—		—			4			—			4		—		2			—
Amortization of prior unrecognized (loss) gain		—		(3	)		—		(2	)		1		(1	)		—			—			—		—		—			—
Other		—		—			—		1			—		—			—			—			—		—		—			—

Total other comprehensive loss (income)	$	2	$	(2	)	$	5	$	11		$	35	$	18		$	1		$	(1	)	$	5	$	—	$	(4	)	$	2

Sensitivity Analysis


	1-Percentage-Point
	Increase				Decrease
	U.S.		Foreign		U.S.		Foreign
	(Dollars in millions)
Effect on postretirement benefit obligation	$	—	$	2	$	—	$	(2	)

Defined Benefit Pension Plans Weighted Average Asset Allocations


	Pension Assets
	September 30
	2011						2010
	U.S.			Foreign			U.S.			Foreign
Asset Category:
Equity securities		57	%		44	%		64	%		44	%
Debt securities		43	%		50	%		36	%		51	%
Cash and other securities		—	%		6	%		—	%		5	%

Total		100	%		100	%		100	%		100	%

Fair Value Of The Pension Plan Assets By Asset Category


			Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Observable Inputs (Level 2)		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Observable Inputs (Level 2)
	Total		US				Non-US
	(Dollars in millions)
Asset Category:
Cash and cash equivalents	$	5	$	—	$	1	$	4	$	—
Direct investments:
U.S. equity securities		13		13		—		—		—
Non-U.S. equity securities		1		1		—		—		—
Non-U.S. government bonds		47		—		—		47		—
Non-U.S. corporate bonds		1		—		—		1		—

Total direct investments		62		14		—		48		—
Investment funds:
Equity funds⁽¹⁾		106		20		—		—		86
Fixed income funds⁽²⁾		93		43		—		—		50
Real estate funds⁽³⁾		1		—		—		—		1
Common and collective investment trust fund⁽⁴⁾		24		—		24		—		—
Money market fund		1		1		—		—		—

Total investment funds		225		64		24		—		137
Alternative investments:
Insurance contracts		8		—		—		—		8

Total alternative investments		8		—		—		—		8

Total pension plan assets	$	300	$	78	$	25	$	52	$	145

⁽¹⁾	The equity funds asset class includes funds that invest in U.S. equities as well as equity securities issued by companies incorporated, listed or domiciled in countries in developed and/or emerging markets. These companies may be in the small-, mid- or large-cap categories.

⁽²⁾

⁽³⁾

⁽⁴⁾

Stock-Based Compensation (Tables)

12 Months Ended

Sep. 30, 2011

Stock Based Compensation

Stock-Based Compensation Expenses


	Years Ended September 30
	2011			2010			2009
	(Dollars in millions)
Cost of Sales	$	5		$	6		$	7
Selling and administrative expenses		9			11			11
Research and technical expenses		1			1			1

Stock-based compensation expense		15			18			19
Income tax benefit		(5	)		(7	)		(7	)

Net stock-based compensation expense	$	10		$	11		$	12

Equity Incentive Plan Activity


	September 30, 2011
	Stock Options							Restricted Stock					Restricted Stock Units
	Total Options			Weighted Average Exercise Price		Weighted Average Grant Date Fair Value		Restricted Stock			Weighted Average Grant Date Fair Value		Restricted Stock Units⁽¹⁾			Weighted Average Grant Date Fair Value
	(Shares in thousands)
Outstanding at September 30, 2010		1,765		$	20.40	$	5.21		829		$	20.81		454		$	23.90
Granted		250			34.64		12.09		—			—		387			34.76
Performance-based adjustment⁽²⁾		—			—		—		—			—		58			28.60
Exercised / Vested		(180	)		23.32		5.67		(820	)		22.61		(4	)		28.63
Cancelled / Forfeited		(63	)		24.74		7.35		(6	)		22.43		(29	)		28.48

Outstanding at September 30, 2011		1,772			21.96		6.06		3			9.56		866			28.89

Exercisable at September 30, 2011		809			20.70

Expected to vest⁽³⁾		940			23.07

⁽¹⁾

⁽²⁾	Represents the incremental number of shares issuable upon vesting of outstanding performance-based restricted stock units, based on the Company achieving performance at a level greater than target under the 2011 performance targets.

⁽³⁾	Stock options expected to vest in the future, net of estimated forfeitures, have a weighted average remaining contractual life of 8.1 years.

Stock Options Outstanding And Vested Options


	Total Options Outstanding		Exercisable Options
Aggregate Intrinsic Value (in millions)	$	5	$	3
Weighted Average Remaining Contractual Term (in years)		7.5		6.7

Weighted-Average Assumptions


	Years Ended September 30
	2011			2010			2009
Expected stock price volatility		43	%		42	%		39	%
Risk free interest rate		1.8	%		2.8	%		0.4	%
Expected life of options (years)		6			6			6
Expected annual dividends per year	$	0.72		$	0.72		$	0.72

Restructuring (Tables)

12 Months Ended

Sep. 30, 2011

Restructuring

Recorded Restructuring Activities


	Years Ended September 30
	2011		2010		2009
	(Dollars in millions)
Cost of sales	$	16	$	36	$	80
Selling and administrative expenses		2		10		5
Research and technical expenses		—		—		2

Total	$	18	$	46	$	87

Restructuring Activities And Related Reserves


	Severance and Employee Benefits			Environmental Remediation			Asset Impairment and Accelerated Depreciation			Asset Sales			Other			Total
	(Dollars in millions)
Reserve at September 30, 2009	$	20		$	1		$	—		$	—		$	—		$	21
Charges		29			2			11			(3	)		7			46
Costs charged against assets and other		—			—			(11	)		—			—			(11	)
Proceeds from sale		—			—			—			3			—			3
Cash paid		(27	)		(2	)		—			—			(7	)		(36	)
Foreign currency translation adjustment		(4	)		—			—			—			—			(4	)

Reserve at September 30, 2010	$	18		$	1		$	—		$	—		$	—		$	19
Charges		8			3			3			(1	)		5			18
Costs charged against assets and other		1			—			(3	)		(4	)		—			(6	)
Proceeds from sale		—			—			—			6			—			6
Cash paid		(17	)		(4	)		—			(1	)		(4	)		(26	)
Foreign currency translation adjustment		(1	)		—			—			—			1			—

Reserve at September 30, 2011	$	9		$	—		$	—		$	—		$	2		$	11

Stockholders' Equity (Tables)

12 Months Ended

Sep. 30, 2011

Stockholders' Equity

Schedule Of Accumulated Other Comprehensive Income (Loss)


	September 30
	2011			2010
	(Dollars in millions)
Foreign currency translation adjustments	$	163		$	144
Unrealized holding gain on investments		1			1
Change in funded status of retirement plans		(58	)		(57	)

Accumulated other comprehensive income	$	106		$	88

Earnings Per Share (Tables)

12 Months Ended

Sep. 30, 2011

Earnings Per Share

Components Of Basic And Diluted Earnings Per Common Share

	Years Ended September 30
	2011			2010			2009
	(In millions, except per share amounts)
Basic EPS:
Net income (loss) attributable to Cabot Corporation	$	236		$	154		$	(77	)
Less: Dividends and dividend equivalents to participating securities		1			1			2
Less: Undistributed earnings allocated to participating securities⁽¹⁾		2			2			—

Earnings (loss) allocated to common shareholders (numerator)	$	233		$	151		$	(79	)

Weighted average common shares and participating securities outstanding		65.4			65.3			65.3
Less: Participating securities⁽¹⁾		0.8			1.5			2.5

Adjusted weighted average common shares (denominator)		64.6			63.8			62.8

Per share amounts—basic:
Income (loss) from continuing operations attributable to Cabot Corporation	$	2.80		$	1.96		$	(1.21	)
Income (loss) from discontinued operations		0.82			0.41			(0.04	)

Net income (loss) attributable to Cabot Corporation	$	3.62		$	2.37		$	(1.25	)

Diluted EPS:
Earnings (loss) allocated to common shareholders	$	233		$	151		$	(79	)
Plus: Earnings allocated to participating securities		3			3			2
Less: Adjusted earnings allocated to participating securities⁽²⁾		(3	)		(3	)		(2	)

Earnings (loss) available to common shares (numerator)	$	233		$	151		$	(79	)

Adjusted weighted average common shares outstanding		64.6			63.8			62.8
Effect of dilutive securities:
Common shares issuable⁽³⁾		0.8			0.5			—

Adjusted weighted average common shares (denominator)		65.4			64.3			62.8

Per share amounts—diluted:
Income (loss) from continuing operations attributable to Cabot Corporation	$	2.77		$	1.94		$	(1.21	)
Income (loss) from discontinued operations		0.80			0.41			(0.04	)

Net income (loss) attributable to Cabot Corporation	$	3.57		$	2.35		$	(1.25	)

⁽¹⁾

⁽²⁾

Undistributed earnings are adjusted for the assumed distribution of dividends to the dilutive securities, which are described in (3) below, and then reallocated to participating securities.

⁽³⁾

Calculation Of Undistributed Earnings


	Years Ended September 30
	2011		2010		2009
	(Dollars in millions)
Calculation of undistributed earnings:
Net income (loss) attributable to Cabot Corporation	$	236	$	154	$	(77	)
Less: Dividends declared on common stock		46		46		46
Less: Dividends and dividend equivalents to participating securities		1		1		2

Undistributed earnings	$	189	$	107	$	(125	)

Allocation of undistributed earnings:
Undistributed earnings allocated to common shareholders	$	187	$	105	$	(125	)
Undistributed earnings allocated to participating securities		2		2		—

Undistributed earnings	$	189	$	107	$	(125	)

Income Taxes (Tables)

12 Months Ended

Sep. 30, 2011

Income Taxes

Income (Loss) Before Income Taxes


	Years ended September 30
	2011			2010		2009
	(Dollars in millions)
Domestic	$	(25	)	$	3	$	(72	)
Foreign		228			163		(27	)

Total	$	203		$	166	$	(99	)

Provision (Benefit) On Income (Loss)


	Years ended September 30
	2011			2010			2009
	(Dollars in millions)
U.S. federal and state:
Current	$	(7	)	$	(8	)	$	(2	)
Deferred		(51	)		(14	)		(32	)

Total		(58	)		(22	)		(34	)

Foreign:
Current		57			51			27
Deferred		7			1			(14	)

Total		64			52			13

Total U.S. and foreign	$	6		$	30		$	(21	)

Reconciliation Using U.S. Statutory Rate


	Years ended September 30
	2011			2010			2009
	(Dollars in millions)
Computed tax expense at the federal statutory rate	$	70		$	58		$	(35	)
Foreign income:
Impact of taxation at different rates, repatriation and other		(29	)		(26	)		(3	)
Impact of repatriation of high tax income		(24	)		—			—
Impact of investment incentive credits		(2	)		(2	)		(1	)
Impact of foreign losses for which a current tax benefit is not available		6			17			30
State taxes, net of federal effect		—			—			—
U.S. and state benefits from research and experimentation activities		(3	)		(1	)		(4	)
Tax audit settlements		(12	)		(15	)		(9	)
Other, net		—			(1	)		1

Total	$	6		$	30		$	(21	)

Components Of Deferred Income Taxes


	September 30
	2011			2010
	(Dollars in millions)
Deferred tax assets:
Depreciation and amortization	$	73		$	67
Pension and other benefits		87			89
Environmental liabilities		3			3
Inventory		12			16
Deferred expenses		11			15
Net operating loss carry-forwards		125			131
Other tax carry-forwards		137			95
Other		28			26

Subtotal		476			442
Valuation allowances		(138	)		(126	)

Total deferred tax assets	$	338		$	316

	September 30
	2011			2010
	(Dollars in millions)
Deferred tax liabilities:
Depreciation and amortization	$	28		$	28
Pension and other benefits		2			4
Unremitted earnings of non-U.S. subsidiaries		18			12
Inventory		3			3
Other		5			6

Total deferred tax liabilities	$	56		$	53

Expiration Dates Of Carryforwards


	NOLs		Other Credits
	(Dollars in millions)
Expiration periods
2012 to 2018	$	132	$	6
2019 and thereafter		131		110
Indefinite carryforward		302		21

Total	$	565	$	137

Reconciliation Of Unrecognized Tax Benefits


	Years ended September 30
	2011			2010			2009
	(Dollars in millions)
Balance at beginning of the year	$	75		$	81		$	80
Additions based on tax provisions related to the current year		2			6			7
Additions for tax positions of prior years		1			3			4
Reductions of tax provisions of prior years		(13	)		(15	)		(10	)

Balance at end of the year	$	65		$	75		$	81

Tabular disclosure of tax positions taken in the tax returns filed or to be filed for which it is more likely than not that the tax position will not be sustained upon examination by taxing authorities (i.e., uncertain tax positions) and other types of income tax contingencies, including: (1) the policy on classification of interest and penalties; (2) a tabular reconciliation of the total amounts of unrecognized tax benefits at the beginning and end of the period; the total amount(s) of: (3) unrecognized tax benefits that, if recognized, would affect the effective tax rate, and (4) interest and penalties recognized in each of the income statement and balance sheet; (5) for positions for which it is reasonably possible that the total amounts unrecognized will significantly change within 12 months of the reporting date the: (i) nature of the uncertainty, (ii) nature of the event that could occur that would cause the change, and (iii) an estimate of the range of the reasonably possible change or a statement that an estimate of the range cannot be made; and (6) a description of tax years that remain subject to examination by major tax jurisdictions.

Tabular disclosure of tax credit carryforwards available to reduce future taxable income, including amounts, expiration dates, limitations on use and the related deferred tax assets and valuation allowances.

Schedule Of Future Minimum Rental Commitments Under Non-Cancelable Leases

Commitments And Contingencies (Tables)

12 Months Ended

Sep. 30, 2011

Commitments And Contingencies


	(Dollars in millions)
2012		19
2013		15
2014		12
2015		11
2016		8
2017 and thereafter		29

Total future minimum rental commitments	$	94

Schedule Of Raw Material Purchased Under Long Term Purchase Agreements


	Years Ended September 30
	2011		2010		2009
	(Dollars in millions)
Core Segment	$	340	$	294	$	136
Performance Segment		18		36		82
Specialty Fluids Segment		—		6		4

Total	$	358	$	336	$	222

Schedule Of Other Long-Term Commitments


	Payments Due by Fiscal Year
	2012		2013		2014		2015		2016		Thereafter		Total
	(Dollars in millions)
Core Segment	$	272	$	245	$	229	$	227	$	200	$	2,705	$	3,878
Performance Segment		16		30		31		30		171		133		411
New Business Segment		1		1		—		—		—		—		2

Total	$	289	$	276	$	260	$	257	$	371	$	2,838	$	4,291

Concentration Of Credit Risk (Tables)

12 Months Ended

Sep. 30, 2011

Concentration Of Credit Risk

Schedule Of Account Receivable


	September 30
	2011		2010
	(Dollars in millions)
Tire manufacturers	$	318	$	259

Financial Information By Segment & Geographic Area (Tables)

12 Months Ended

Sep. 30, 2011

Financial Information By Segment & Geographic Area

Schedule Of Performance Segment


	Years Ended September 30
	2011		2010		2009
	(Dollars in millions)
Performance Products Business	$	626	$	531	$	410
Fumed Metal Oxides Business		254		252		210

Total Performance Segment	$	880	$	783	$	620

Schedule Of New Business Segment


	Years Ended September 30
	2011		2010		2009
	(Dollars in millions)
Inkjet Colorants Business	$	65	$	57	$	46
Aerogel Business		24		24		15
Cabot Superior MicroPowders Business		11		7		4
Cabot Elastomer Composites Business		17		17		5

Total New Business Segment	$	117	$	105	$	70

Financial Information By Segment


	Core Segment		Performance Segment		New Business Segment			Specialty Fluids Segment		Segment Total		Unallocated and Other^{(1), (3)}			Consolidated Total
	(Dollars in millions)
Years Ended September 30
2011
Revenues from external customers⁽²⁾		1,952		880		117			69		3,018		84			3,102
Depreciation and amortization		80		37		11			3		131		8			139
Equity in earnings of affiliated companies		7		1		—			—		8		—			8
Income (loss) from continuing operations before taxes⁽³⁾		183		140		9			22		354		(151	)		203
Assets⁽⁴⁾		1,509		661		90			101		2,361		780			3,141
Investment in equity-based affiliates		50		10		—			—		60		—			60
Total expenditures for additions to long-lived assets⁽⁵⁾		126		99		7			3		235		6			241
2010
Revenues from external customers⁽²⁾		1,660		783		105			81		2,629		87			2,716
Depreciation and amortization		74		35		10			2		121		16			137
Equity in earnings of affiliated companies		6		1		—			—		7		—			7
Income (loss) from continuing operations before taxes⁽³⁾		139		125		15			35		314		(148	)		166
Assets⁽⁴⁾		1,277		544		93			95		2,009		877			2,886
Investment in equity-based affiliates		51		10		—			—		61		—			61
Total expenditures for additions to long-lived assets⁽⁵⁾		62		38		3			1		104		3			107
2009
Revenues from external customers⁽²⁾		1,283		620		70			64		2,037		71			2,108
Depreciation and amortization		99		46		11			2		158		6			164
Equity in earnings of affiliated companies		5		—		—			—		5		—			5
Income (loss) from continuing operations before taxes⁽³⁾		21		25		(3	)		18		61		(160	)		(99	)
Assets⁽⁴⁾		1,215		507		93			78		1,893		783			2,676
Investment in equity-based affiliates		56		4		—			—		60		—			60
Total expenditures for additions to long-lived assets⁽⁵⁾		72		32		4			1		109		1			110

⁽¹⁾

⁽²⁾	Unallocated and other reflects royalties paid by equity affiliates, external shipping and handling fees, and the impact of the corporate adjustment for unearned revenue.


	Years Ended September 30
	2011			2010		2009
	(Dollars in millions)
Royalties received from equity affiliates and other operating revenues	$	(2	)	$	7	$	6
Shipping and handling fees		86			80		65

Total	$	84		$	87	$	71

⁽ ³ ⁾

Income (loss) from continuing operations before taxes for Unallocated and Other includes:


	Years Ended September 30
	2011			2010			2009
	(Dollars in millions)
Interest expense	$	(39	)	$	(40	)	$	(30	)
Certain items^(a)		(19	)		(53	)		(92	)
Equity in net income of affiliated companies^(b)		(8	)		(7	)		(5	)
Unallocated corporate costs^(c)		(53	)		(48	)		(36	)
General unallocated (expense) income^(d)		(32	)		—			3

Total	$	(151	)	$	(148	)	$	(160	)

^(a)

^(b)

Equity in net income of affiliated companies is included in segment EBIT and is removed from Unallocated and other to reconcile to income (loss) from operations before taxes.

^(c)

Unallocated corporate costs are not controlled by the segments and primarily benefit corporate interests.

^(d)

⁽⁴⁾	Unallocated and Other assets includes cash, marketable securities, cost investments, income taxes receivable, deferred taxes, headquarters' assets, and Current and Non-current assets held for sale.

⁽⁵⁾	Expenditures for additions to long-lived assets include total equity and other investments, property, plant and equipment, intangible assets and assets held for rent.

Revenues From External Customers And Long-Lived Asset Information By Geographic Area


	United States		China		Other Foreign Countries		Consolidated Total
	(Dollars in millions)
Years Ended September 30,
2011
Revenues from external customers	$	589	$	554	$	1,959	$	3,102
Long-lived assets⁽¹⁾	$	240	$	280	$	650	$	1,170

2010
Revenues from external customers	$	546	$	458	$	1,712	$	2,716
Long-lived assets⁽¹⁾	$	233	$	210	$	640	$	1,083

2009
Revenues from external customers	$	332	$	281	$	1,495	$	2,108
Long-lived assets⁽¹⁾	$	320	$	201	$	593	$	1,114

⁽¹⁾	Long-lived assets include total equity and other investments, net property, plant and equipment, net intangible assets and assets held for rent.

Tabular disclosure of the profit or loss and total assets for each reportable segment. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.

Unaudited Quarterly Financial Information

Unaudited Quarterly Financial Information (Tables)

12 Months Ended

Sep. 30, 2011

Schedule Of Quarterly Financial Information


	Quarter Ended
	December			March			June			September			Year
	(Dollars in millions, except per share amounts and ratios)
Fiscal 2011
Consolidated Net Income
Net sales and other operating revenues	$	694		$	739		$	836		$	833		$	3,102

Gross profit		131			134			152			141			558
Selling and administrative expenses		63			62			61			63			249
Research and technical expenses		15			18			16			17			66

Income from operations		53			54			75			61			243
Net interest expense and other charges		(7	)		(6	)		(13	)		(14	)		(40	)

Income from continuing operations before taxes		46			48			62			47			203
Benefit (provision) for income taxes		15			(9	)		(10	)		(2	)		(6	)
Equity in earnings of affiliated companies		3			1			2			2			8
Income from discontinued operations, net of tax		16			16			13			8			53

Net income		80			56			67			55			258
Net income attributable to noncontrolling interests, net of tax		5			5			7			5			22

Net income attributable to Cabot Corporation	$	75		$	51		$	60		$	50		$	236

Income per share - diluted:
Income from continuing operations	$	0.88		$	0.52		$	0.73		$	0.64		$	2.77
Income from discontinued operations		0.25			0.24			0.19			0.12			0.80

Net income attributable to Cabot Corporation	$	1.13		$	0.76		$	0.92		$	0.76		$	3.57


	Quarter Ended
	December			March			June			September			Year
	(Dollars in millions, except per share amounts and ratios)
Fiscal 2010
Consolidated Net Income
Net sales and other operating revenues	$	634		$	676		$	706		$	700		$	2,716

Gross profit		126			131			136			117			510
Selling and administrative expenses		67			58			62			54			241
Research and technical expenses		17			18			14			16			65

Income from operations		42			55			60			47			204
Net interest expense and other charges		(9	)		(15	)		(6	)		(8	)		(38	)

Income from continuing operations before taxes		33			40			54			39			166
Benefit (provision) for income taxes		(8	)		3			(14	)		(11	)		(30	)
Equity in earnings of affiliated companies		3			1			1			2			7
Income from discontinued operations, net of tax		6			3			10			7			26

Net income		34			47			51			37			169
Net income attributable to noncontrolling interests, net of tax		5			4			4			2			15

Net income attributable to Cabot Corporation	$	29		$	43		$	47		$	35		$	154

Income per share - diluted:
Income from continuing operations	$	0.36		$	0.59		$	0.57		$	0.42		$	1.94
Income from discontinued operations		0.08			0.06			0.15			0.12			0.41

Net income attributable to Cabot Corporation	$	0.44		$	0.65		$	0.72		$	0.54		$	2.35

Significant Accounting Policies (Narrative) (Details) ¥ in Millions, $ in Millions	12 Months Ended
	Sep. 30, 2011 USD ($) years	Sep. 30, 2010 USD ($)	Sep. 30, 2009 USD ($)	Sep. 30, 2011 CNY (¥)	Sep. 30, 2011 USD ($)	Sep. 30, 2010 CNY (¥)	Sep. 30, 2010 USD ($)
Significant Accounting Policies [Line Items]
Investments in equity affiliates				49.00%	49.00%
Capitalized interest	$ 2	$ 1	$ 4
Asset retirement obligation reserve					$ 7		$ 10
Foreign currency transaction losses (gains)	$ 6		15
Accounts and notes receivable, net					$ 659		540
Chance of utilizing the associated benefit for valuation allowances, maximum	50.00%
Maximum [Member]
Significant Accounting Policies [Line Items]
Investments in equity affiliates				50.00%	50.00%
Amortization of intangible assets	$ 1	1	1
Foreign currency transaction losses (gains)		(1)
Charges on sale of notes receivables	$ 1
Minimum [Member]
Significant Accounting Policies [Line Items]
Investments in equity affiliates				20.00%	20.00%
Building [Member]
Significant Accounting Policies [Line Items]
Minimum useful life of property, plant and equipment \| years	20
Maximum useful life of property, plant and equipment \| years	25
Machinery And Equipment [Member]
Significant Accounting Policies [Line Items]
Minimum useful life of property, plant and equipment \| years	10
Maximum useful life of property, plant and equipment \| years	20
Other Fixed Assets [Member]
Significant Accounting Policies [Line Items]
Minimum useful life of property, plant and equipment \| years	3
Maximum useful life of property, plant and equipment \| years	25
Notes Receivable [Member]
Significant Accounting Policies [Line Items]
Accounts and notes receivable, net				¥ 380	$ 60	¥ 143	$ 21
Charges on sale of notes receivables		$ 2	$ 1

Significant Accounting Policies (Percentages Of Total Net Sales And Other Operating Revenues) (Details)	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Segment Reporting Information [Line Items]
Revenue, by segment	65.00%	63.00%	63.00%
Performance Segment [Member]
Segment Reporting Information [Line Items]
Revenue, by segment	29.00%	30.00%	31.00%
New Business Segment [Member]
Segment Reporting Information [Line Items]
Revenue, by segment	4.00%	4.00%	3.00%
Specialty Fluids Segment [Member]
Segment Reporting Information [Line Items]
Revenue, by segment	2.00%	3.00%	3.00%

Discontinued Operations (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Initial cash payment, transactions closes	$ 175.0
Interest-bearing two-year promissory notes	175.0
Contingent payment, based on future performance of the acquired business	$ 11.5
Contingent payment, percentage of quarterly cash payments of adjusted EBITDA	50.00%
Promissory notes, interest rate	10.84%
Total prepayment value of promissory notes	$ 215.0
Settlements net charges		$ 0.0
Maximum [Member]
Settlements net charges	1.0		$ 1.0
Minimum [Member] \| Global Advanced Metals Pty Ltd [Member]
Total consideration	$ 401.5

Discontinued Operations (Components Income (Loss) From Discontinued Operations) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Discontinued Operations
Net sales and other operating revenues									$ 201	$ 177	$ 135
Income (loss) from operations before income taxes									84	42	(3)
(Provision) benefit for income taxes									(31)	(16)	1
Income (loss) from discontinued operations, net of tax	$ 8	$ 13	$ 16	$ 16	$ 7	$ 10	$ 3	$ 6	$ 53	$ 26	$ (2)

Overall income (loss) from a disposal group that is classified as a component of the entity, before income tax, reported as a separate component of income before extraordinary items. Includes the following (before income tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 144
-Paragraph 43
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 144
-Paragraph 47
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 46
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 3
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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This element represents the overall income (loss) from a disposal group that is classified as a component of the entity, net of income tax, reported as a separate component of income before extraordinary items before deduction or consideration of the amount which may be allocable to noncontrolling interests, if any. Includes the following (net of tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 144
-Paragraph 43
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 144
-Paragraph 47
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 29
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 5
-Section 03
-Paragraph 15

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 13
-Article 7

Reference 6: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
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-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e957-107759

Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 944
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-Paragraph 1
-Subparagraph (SX 210.7-04.12)
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-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Discontinued Operations (Schedule Of Assets And Liabilities Held For Sale) (Details) - USD ($) $ in Millions	Sep. 30, 2011	Sep. 30, 2010
Discontinued Operations
Accounts and notes receivable, net of reserve for doubtful accounts	$ 41	$ 36
Inventories	64	66
Prepaid expenses and other current assets	1	1
Total current assets held for sale	106	103
Net property, plant and equipment	39	38
Other assets		2
Total noncurrent assets held for sale	39	40
Accounts payable and accrued liabilities	12	16
Total current liabilities held for sale	12	16
Other liabilities	6	6
Total noncurrent liabilities held for sale	$ 6	$ 6

Inventories (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Inventories [Line Items]
Inventory valued under the LIFO method	8.00%				10.00%				8.00%	10.00%
Inventory, LIFO reserve	$ 53				$ 35				$ 53	$ 35
Decrease in cost of goods sold									$ 0	$ 0	$ 5
Effect of LIFO inventory liquidation on income											$ 3
Liquidation of LIFO inventory, resulted per diluted common share	$ 0.76	$ 0.92	$ 0.76	$ 1.13	$ 0.54	$ 0.72	$ 0.65	$ 0.44	$ 3.57	$ 2.35	$ (1.25)
Obsolete inventory reserve	$ 10				$ 10				$ 10	$ 10
Inventory Valuation And Obsolescence [Member]
Inventories [Line Items]
Liquidation of LIFO inventory, resulted per diluted common share									$ 0.00	$ 0.00	$ 0.06

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

The amount of the valuation account as of the balance sheet date which reduces the carrying amount of inventory to net realizable value; takes into consideration such factors as market value, excessive quantities based on expected sales, technological obsolescence, and shrinkage. May also provide for estimated product returns or price concessions pertaining to product cost.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 6
-Subparagraph a
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 3
-Section A
-Paragraph 9
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 4
-Paragraph 14
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 4
-Paragraph 8, 9, 14
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 09
-Article 12

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6386567&loc=d3e3927-108312

Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 330
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-Paragraph 2
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690

Inventories (Components Of The Company's Inventories) (Details) - USD ($) $ in Millions	Sep. 30, 2011	Sep. 30, 2010
Inventories
Raw materials	$ 120	$ 94
Work in process	3	3
Finished goods	233	179
Other	37	31
Total	$ 393	$ 307

Investments (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Investments (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Investments
Investments in equity affiliates	$ 60	$ 61	$ 60
Cash dividends declared by equity investments	$ 5	$ 6	$ 1

Investments (Equity Method Investments Of Income Statement And Balance Sheet Information) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Investments
Net sales	$ 312	$ 363	$ 172
Gross profit	55	50	33
Net income	18	20	10
Current assets	109	141	87
Non-current assets	55	73	64
Current liabilities	38	32	34
Non-current liabilities	3	50	7
Net assets	$ 123	$ 132	$ 110

The amount of current assets reported by an equity method investment of the entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 18
-Subparagraph f
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 20
-Subparagraph d
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph bb
-Article 1

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph w
-Article 1

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 4
-Section 08
-Paragraph g
-Subparagraph 1, 2

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(g))
-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33912-111571

The amount of current liabilities reported by an equity method investment of the entity.

The amount of gross profit (loss) reported by an equity method investment of the entity.

The amount of net income (loss) reported by an equity method investment of the entity.

The amount of noncurrent assets reported by an equity method investment of the entity.

The amount of noncurrent liabilities reported by an equity method investment of the entity.

Property, Plant And Equipment (Components Of Property, Plant And Equipment) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Property, Plant And Equipment
Land and land improvements	$ 73	$ 69
Buildings	479	475
Machinery and equipment	2,076	2,011
Other	162	221
Construction in progress	177	102
Total property, plant and equipment	2,967	2,878
Less: accumulated depreciation	(1,931)	(1,941)
Net property, plant and equipment	1,036	937
Depreciation expense	$ 138	$ 137	$ 164

Goodwill And Other Intangible Assets (Narrative) (Details) $ in Millions	6 Months Ended	12 Months Ended
	Mar. 31, 2011 USD ($)	Sep. 30, 2011 USD ($) years	Sep. 30, 2010 USD ($)	Sep. 30, 2009 USD ($)	Jul. 31, 2010 USD ($)
Goodwill		$ 40	$ 39	$ 37
Goodwill annual impairment	$ 0
Indefinite-lived intangible assets		$ 0
Useful life of intangible assets, minimum (years) \| years		6
Useful life of intangible assets, maximum (years) \| years		14
Useful life of intangible assets \| years		12
Cabot Security Materials Inc [Member]
Voting percentage					100.00%
Total consideration					$ 5
Maximum [Member]
Amortization of intangible assets		$ 1	$ 1	$ 1
Amortization of intangible assets, year one		1
Amortization of intangible assets, year two		1
Amortization of intangible assets, year three		1
Amortization of intangible assets, year four		1
Amortization of intangible assets, year five		$ 1

Goodwill And Other Intangible Assets (Schedule of Goodwill Balances) (Details) - USD ($)
$ in Millions

12 Months Ended

Sep. 30, 2011

Sep. 30, 2010

$ 39

$ 37

^[1]

Rubber Blacks Business [Member]

^[1]

Fumed Metal Oxides Business [Member]

^[1]

Security Materials Business [Member]

^[1]

$ 2

$ 1

[1]	Goodwill acquired relates to the acquisition of Oxonica Materials Inc. in Security Materials.

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph e
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 43
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph l
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
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-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6905597&loc=d3e13816-109267

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 72
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph e
-Clause 1
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 34
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

The increase (decrease) in the recorded value of goodwill for foreign currency translation adjustments and purchase accounting adjustments needed to revise the carrying amount of goodwill to fair value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Subparagraph e
-Paragraph 45
-Clause 6
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=6905597&loc=d3e13816-109267

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 72
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Subparagraph e
-Paragraph 45
-Clause 3
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Subparagraph e
-Paragraph 45
-Clause 7
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Other Intangible Assets [Member]

Goodwill And Other Intangible Assets (Schedule Of Finite-Lived Intangible Assets) (Details) - USD ($)
$ in Millions

Sep. 30, 2011

Sep. 30, 2010

Gross Carrying Value

$ 5

Accumulated Amortization

(2)

Net Intangible Assets

Patents [Member]

Gross Carrying Value

Accumulated Amortization

(2)

Net Intangible Assets

Gross Carrying Value

^[1]

Accumulated Amortization

^[1]

Net Intangible Assets

^[1]

$ 3

[1]	Other intangible assets relates to the acquisition of Oxonica Materials Inc. in Security Materials in fiscal 2010.

Accounts Payable, Accrued Liabilities And Other Liabilities (Components Of Accounts Payable And Accrued Liabilities) (Details) - USD ($) $ in Millions	Sep. 30, 2011	Sep. 30, 2010
Accounts Payable, Accrued Liabilities And Other Liabilities
Accounts payable	$ 330	$ 292
Accrued employee compensation	44	58
Accrued severance and restructuring	11	21
Other accrued liabilities	76	60
Total	$ 461	$ 431

Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Accounts Payable, Accrued Liabilities And Other Liabilities (Components Of Other Long-Term Liabilities) (Details) - USD ($) $ in Millions	Sep. 30, 2011	Sep. 30, 2010
Accounts Payable, Accrued Liabilities And Other Liabilities
Employee benefit plan liabilities	$ 161	$ 160
Non-current tax liabilities	50	63
Financial instrument liabilities	39	39
Other accrued liabilities	49	56
Total	$ 299	$ 318

Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and which are expected to be extinguished or otherwise disposed of after one year or beyond the normal operating cycle, if longer, net of the effects of master netting arrangements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 3
-Section A
-Paragraph 7
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 10
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FIN39-1
-Paragraph 10A, 10B
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 4, 17
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13433-108611

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13495-108611

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 6
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 3
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6410544&loc=d3e1703-114919

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2410-114920

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2417-114920

Principal Payments On Long Term Debt [Member]

Debt And Other Obligations (Narrative) (Details) $ in Millions	1 Months Ended	12 Months Ended
	Aug. 31, 2011 USD ($)	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Sep. 30, 2009 USD ($)
Debt instrument, interest rate		10.84%
Long-term debt		$ 613	$ 623
Issuance of notes, discount recorded		2	2
Dividends paid to ESOP		2	3	$ 3
Interest payments from ESOP		1	2	$ 2
Capital lease obligations		15	3
Repayments of long-term capital lease obligations		$ 29
Repayment period of capital lease obligation, years		20
Original cost of capital lease assets		$ 24	11
Accumulated depreciation of assets under capital leases		10	$ 8
Payment towards imputed interest		14
Standby letters of credit, outstanding amount		37
Issued under the credit agreement		29
Additional issuance, other standby letters of credit		8
Unsecured short term notes payable to bank		$ 86
Weighted-average interest rate on short-term notes payable		5.30%	4.60%
Revolving Credit Facility [Member]
Revolving credit facility, outstanding amount		$ 29
Additional line of credit facility		$ 750
Interest rates are based upon LIBOR plus a spread, spread		1.125%
Revolving Credit Facility Expiry August 2016 [Member]
Revolving credit facility, outstanding amount	$ 550
Revolving credit facility, agreement period	August 2016
Revolving Credit Facility Expiry 2011 [Member]
Revolving credit facility, outstanding amount	$ 450
Revolving credit facility, agreement period	June 2014
Chinese Renminbi Notes [Member]
Long-term debt			$ 20
5% Notes Due 2016 [Member]
Debt maturity date				Oct. 01, 2016
Debt instrument, interest rate				5.00%
Public notes issued				$ 300
Proceeds from issuance of debt notes		$ 296
Issuance of notes, discount recorded				2
5.25% Eurobond, Due 2013 [Member]
Debt maturity date		Sep. 01, 2013
Debt instrument, interest rate		5.25%
Proceeds from issuance of debt notes		$ 175
Issuance of notes, discount recorded		$ 1
8.29% ESOP Note Due 2013 [Member]
Debt maturity date		Dec. 31, 2013
Debt instrument, interest rate		8.29%
Long-term debt		$ 14	20
Employer contribution to ESOP to service the debt		4	4	$ 4
Unsecured Debt [Member]
Unsecured short term notes payable to bank			29
Fixed Rate Debt [Member]
Unsecured medium term notes outstanding issued		$ 83	98
Maturity of the total outstanding medium term notes, years		6.5
Weighted average interest of medium term notes		7.90%
Standby Letter Of Credit [Member]
Debt instrument due, year		2012
Fixed Rate Debt [Member]
Long-term debt		$ 585	606
Unsecured medium term notes outstanding issued		$ 83	98
Fixed Rate Debt [Member] \| 5% Notes Due 2016 [Member]
Debt instrument, interest rate		5.00%
Long-term debt		$ 300	300
Debt instrument due, year		2016
Fixed Rate Debt [Member] \| 5.25% Eurobond, Due 2013 [Member]
Debt instrument, interest rate		5.25%
Long-term debt		$ 178	179
Debt instrument due, year		2013
Fixed Rate Debt [Member] \| 8.29% ESOP Note Due 2013 [Member]
Debt instrument, interest rate		8.29%
Long-term debt		$ 14	$ 20
Debt instrument due, year		2013
Employee Stock Ownership Plan [Member] \| 8.29% ESOP Note Due 2013 [Member]
Long-term debt		$ 75

Debt And Other Obligations (Schedule Of Long-Term Obligations) (Details) - USD ($)	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Debt instrument, face amount	$ 175,000,000
Capital lease obligations	15,000,000	$ 3,000,000
Unamortized debt discount	(2,000,000)	(2,000,000)
Total debt	613,000,000	623,000,000
Less current portion on long-term debt	(57,000,000)	(23,000,000)
Total long-term debt	$ 556,000,000	600,000,000
Debt instrument, interest rate	10.84%
5% Notes Due 2016 [Member]
Unamortized debt discount			$ (2,000,000)
Debt instrument, interest rate			5.00%
5.25% Eurobond, Due 2013 [Member]
Unamortized debt discount	$ (1,000,000)
Debt instrument, interest rate	5.25%
8.29% ESOP Note Due 2013 [Member]
Total debt	$ 14,000,000	20,000,000
Debt instrument, interest rate	8.29%
6.10% Chinese Renminbi Notes Due 2012 [Member]
Debt instrument, interest rate	6.10%
Debt instrument due, year	2012
2% Other Note Due 2027 [Member]
Debt instrument, interest rate	2.00%
Debt instrument due, year	2027
Payment On Capital Lease Obligations [Member]
Debt instrument maturity, maximum range	2031
Variable Rate Debt [Member]
Total debt	$ 15,000,000	16,000,000
Variable Rate Debt [Member] \| Revolving Credit Facility Expiry 2016 [Member]
Debt instrument, face amount	$ 550,000,000
Debt instrument due, year	2016
Variable Rate Debt [Member] \| Chinese Renminbi Notes, due Through 2012 [Member]
Total debt	$ 15,000,000	16,000,000
Debt instrument, interest rate	5.40%
Debt instrument maturity, maximum range	2012
Fixed Rate Debt [Member]
Medium Term Notes	$ 83,000,000	98,000,000
Total debt	585,000,000	606,000,000
Fixed Rate Debt [Member] \| 5% Notes Due 2016 [Member]
Total debt	$ 300,000,000	300,000,000
Debt instrument, interest rate	5.00%
Debt instrument due, year	2016
Fixed Rate Debt [Member] \| 7.26% Notes Due 2011 [Member]
Medium Term Notes		15,000,000
Debt instrument, interest rate	7.26%
Debt instrument due, year	2011
Fixed Rate Debt [Member] \| 7.70% - 8.28% Notes Due 2012 [Member]
Medium Term Notes	$ 30,000,000	30,000,000
Debt instrument interest rate, minimum	7.70%
Debt instrument interest rate, maximum	8.28%
Debt instrument maturity, minimum range	2012
Fixed Rate Debt [Member] \| 7.42% Note Due 2018 [Member]
Medium Term Notes	$ 30,000,000	30,000,000
Debt instrument, interest rate	7.42%
Debt instrument due, year	2018
Fixed Rate Debt [Member] \| 8.346% - 8.47% Notes Due 2022 [Member]
Medium Term Notes	$ 15,000,000	15,000,000
Debt instrument interest rate, minimum	8.346%
Debt instrument interest rate, maximum	8.47%
Debt instrument due, year	2022
Fixed Rate Debt [Member] \| 6.57% - 7.28% Notes Due 2027 [Member]
Medium Term Notes	$ 8,000,000	8,000,000
Debt instrument interest rate, minimum	6.57%
Debt instrument interest rate, maximum	7.28%
Debt instrument due, year	2027
Fixed Rate Debt [Member] \| 5.25% Eurobond, Due 2013 [Member]
Total debt	$ 178,000,000	179,000,000
Debt instrument, interest rate	5.25%
Debt instrument due, year	2013
Fixed Rate Debt [Member] \| 8.29% ESOP Note Due 2013 [Member]
Total debt	$ 14,000,000	20,000,000
Debt instrument, interest rate	8.29%
Debt instrument due, year	2013
Fixed Rate Debt [Member] \| 6.10% Chinese Renminbi Notes Due 2012 [Member]
Total debt	$ 5,000,000	4,000,000
Fixed Rate Debt [Member] \| 2% Other Note Due 2027 [Member]
Total debt	$ 5,000,000	$ 5,000,000

Debt And Other Obligations (Schedule Of Future Years Payment) (Details)
$ in Millions

Sep. 30, 2011

USD ($)

Future Years Payment [Line Items]

$ 57

183

301

612

Future Years Payment [Line Items]

2012

^[1]

2013

182

^[1]

2014

^[1]

2015

^[1]

2016

300

^[1]

Thereafter

^[1]

Payment On Capital Lease Obligations [Member]

597

^[1]

Future Years Payment [Line Items]

$ 15

[1]	Payment of long-term debt excludes settlements of cross currency swaps.

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Fair value of assets, land	$ 6
Recorded impairment charge		$ 2
Fair Value, Assets And Liabilities Measured On Nonrecurring Basis, Losses [Member]
Fair value of assets, land		$ 6
Maximum [Member]
Additional Impairment Charge	$ 1

Fair Value Measurements (Schedule Of Fair Value Of Derivatives, Net Of Legal Right To Offset Derivative) (Details) - Significant Observable Inputs (Level 2) [Member] - USD ($)
$ in Millions

Sep. 30, 2011

Sep. 30, 2010

Guaranteed investment contract

^[1]

$ 14

Derivatives assets relating to interest rates

^[2]

Total assets at fair value

Derivatives liabilities relating to foreign currency

^[2]

Hedged long-term debt

Total liabilities at fair value

$ 102

$ 119

[1]	Included in "Other assets" in the Consolidated Balance Sheets.
[2]	Included in "Prepaid expenses and other current assets", "Other assets", "Accounts payable and accrued liabilities" and "Other liabilities" in the Consolidated Balance Sheets.

Fair Value Of Financial Instruments (Carrying Amounts And Fair Values Of Company's Financial Instruments) (Details) - USD ($) $ in Millions	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009	Sep. 30, 2008
Cash and cash equivalents, Carrying Amount	$ 286	$ 387	$ 304	$ 129
Cash and cash equivalents, Fair Value	286	387
Accounts and notes receivable, Carrying Amount	659	540
Accounts and notes receivable, Fair Value	659	540
Derivative instruments, Carrying Amount	1	2
Derivative instruments, Fair Value	1	2
Notes payable to banks, Carrying Amount	86	29
Notes payable to banks, Fair Value	86	29
Accounts payable and accrued liabilities, Carrying Amount	461	431
Accounts payable and accrued liabilities, Fair Value	461	431
Long-term debt, Carrying Amount	613	623
Capital lease obligations, Carrying Amount	15	3
Capital lease obligations, Fair Value	15	3
Derivative instruments, Carrying Amount	39	39
Derivative instruments, Fair Value	39	39
Fixed Rate [Member]
Long-term debt, Carrying Amount	585	604
Long-term debt, Fair Value	633	661
Floating Rate [Member]
Long-term debt, Carrying Amount	15	16
Long-term debt, Fair Value	$ 15	$ 16

Financial Instruments (Narrative) (Details) $ in Millions, ¥ in Billions	3 Months Ended	12 Months Ended
	Dec. 31, 2009 USD ($)	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Sep. 30, 2009 USD ($)	Dec. 31, 2009 JPY (¥)	Dec. 31, 2009 USD ($)
Maximum remaining maturity of foreign currency derivatives, days		30
Number of open derivatives designated as net investment hedges		no
Notional amount of swap					¥ 2.5	$ 20
Cash settlement payment	$ 7
Gains or losses reclassified from accumulated other comprehensive income to earnings			$ 0	$ 0
Foreign currency exchange rate, remeasurement income (loss)		$ (2)	(14)
Bond held by one of Cabot's European subsidiaries		175	175
Loss related to investment hedge		27	27
Forward Foreign Currency Contracts [Member]
Gain (loss) on foreign currency derivative instruments not designated as hedging instruments		3	7
Currency Swap [Member]
Gain (loss) on foreign currency derivative instruments not designated as hedging instruments		$ 16	$ 1

Financial Instruments (Interest Rate Risk Management) (Details) - USD ($)

Sep. 30, 2011

Sep. 30, 2010

Percentage of debt hedged by interest rate derivatives

20.00%

Notional amount of interest rate fair value hedge derivatives

$ 175,000,000

35,000,000

$ 35,000,000

Medium Term Notes [Member]

Notional amount of interest rate fair value hedge derivatives

^[1]

15,000,000

Medium Term Notes With Notional Amount Of 8 Million [Member]

Notional amount of interest rate fair value hedge derivatives

8,000,000

Interest Rate Swap One [Member] | Medium Term Notes With Notional Amount Of 5 Million [Member]

Notional amount of interest rate fair value hedge derivatives

5,000,000

Interest Rate Swap Two [Member] | Medium Term Notes With Notional Amount Of 5 Million [Member]

Notional amount of interest rate fair value hedge derivatives

5,000,000

Interest Rate Swap Three [Member] | Medium Term Notes With Notional Amount Of 5 Million [Member]

Notional amount of interest rate fair value hedge derivatives

$ 5,000,000

[1]	Cabot's interest rate swap derivative instrument and the hedged debt borrowing matured during fiscal 2011.

Financial Instruments (Foreign Currency Risk Management) (Details)
€ in Millions, ¥ in Millions

Sep. 30, 2011

JPY (¥)

Sep. 30, 2011

EUR (€)

Sep. 30, 2011

USD ($)

Sep. 30, 2010

JPY (¥)

Sep. 30, 2010

EUR (€)

Sep. 30, 2010

USD ($)

$ 175,000,000

Eurobond 20% [Member]

Percentage of debt hedged by cross currency swaps

$ 175,000,000

20.00%

Notional amount of foreign currency derivative instruments not designated as hedging instruments

€ 31

$ 35,000,000

€ 31

$ 35,000,000

Eurobond 80% [Member]

Percentage of debt hedged by cross currency swaps

$ 175,000,000

80.00%

Notional amount of foreign currency derivative instruments not designated as hedging instruments

€ 124

$ 140,000,000

€ 124

140,000,000

Forward Foreign Currency Contracts [Member]

Notional amount of foreign currency derivative instruments not designated as hedging instruments

^[1]

$ 54,000,000

$ 23,000,000

Notional Amount of Foreign Currency Cash Flow Hedge Derivatives | ¥

¥ 12

^[2]

[1]	Cabot's forward foreign exchange contracts are denominated primarily in the Australian dollar, British pound sterling, Canadian dollar, Euro, and Japanese yen.
[2]	Cabot's forward foreign exchange contracts designated as cash flow hedges were entered into during fiscal 2011.

Financial Instruments (Commodity Risk Management) (Details) - EUR (€) € in Millions	Sep. 30, 2011	Sep. 30, 2010
EUAs [Member]
Notional amount of commodity risk derivatives	€ 1	€ 2
CERs [Member]
Notional amount of commodity risk derivatives	€ 1	€ 2

Financial Instruments (Schedule Of Derivative Instruments In Statement Of Financial Position, Fair Value) (Details) - USD ($)
$ in Millions

Sep. 30, 2011

Sep. 30, 2010

$ 5

$ 7

Other Liabilities [Member] | Interest Rate Risk Management [Member]

Interest rate contracts with right of offset

Designated As Hedging Instrument [Member]

Designated As Hedging Instrument [Member] | Interest Rate Risk Management [Member]

Designated As Hedging Instrument [Member] | Prepaid Expenses And Other Current Assets, Other assets, And Other liabilities [Member] | Interest Rate Risk Management [Member]

Designated As Hedging Instrument [Member] | Other Liabilities [Member] | Interest Rate Risk Management [Member]

^[1]

Not Designated As Hedging Instrument [Member]

Not Designated As Hedging Instrument [Member] | Prepaid Expenses And Other Current Assets And Other Assets [Member] | Foreign Currency Risk Management [Member]

Not Designated As Hedging Instrument [Member] | Prepaid Expenses And Other Current Assets And Other Assets [Member] | Commodity Risk Management [Member]

^[2]

Not Designated As Hedging Instrument [Member] | Accounts Payable And Accrued Liabilities, And Other Liabilities [Member] | Foreign Currency Risk Management [Member]

^[2]

^[1]

$ 41

$ 42

[1]	Contracts of $3 million and $4 million presented on a gross basis in this table at September 30, 2011 and 2010, respectively, have the legal right to offset against other types of contracts with a common counterparty and, therefore, are presented on a net basis in noncurrent "Other liabilities" in the consolidated balance sheet.
[2]	Contracts in an asset and liability position presented on a gross basis in this table have the legal right of offset and, therefore, are presented on a net basis in "Prepaid expenses and other current assets" and noncurrent "Other assets" in the consolidated balance sheet.

Venezuela (Details) $ in Millions, in Millions	12 Months Ended
Venezuela (Details) $ in Millions, in Millions	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Sep. 30, 2011 VEF ( )	Sep. 30, 2011 USD ($)	Jan. 31, 2011 / $	Mar. 31, 2010 / $	Jan. 31, 2010 / $
Equity method investment, ownership percentage			49.00%	49.00%
Operating affiliate investment \| $				$ 26
Due from affiliates, dividends receivable			21	$ 5
Venezuelan Bolivar exchange rate to one USD						4.30
Foreign currency exchange rate, remeasurement income (loss) \| $	$ (2)	$ (14)
Parallel Rate [Member]
Foreign currency exchange rate, remeasurement income (loss) \| $	1	0
Essential Rate [Member]
Venezuelan Bolivar exchange rate to one USD							2.60
Non-Essentials Rate [Member]
Venezuelan Bolivar exchange rate to one USD							4.30
Prior To Currency Exchange Rate Adjustment [Member] \| Essential Rate [Member]
Venezuelan Bolivar exchange rate to one USD					2.60
After Currency Exchange Rate Adjustment [Member] \| Essential Rate [Member]
Venezuelan Bolivar exchange rate to one USD					4.30
Devaluation Of The Bolivar [Member]
Venezuelan Bolivar exchange rate to one USD							2.15
Maximum [Member]
Equity method investment, ownership percentage			50.00%	50.00%
Translation gains or losses \| $	$ 1	$ 1

Employee Benefit Plans (Narrative) (Details) - USD ($)	12 Months Ended
Employee Benefit Plans (Narrative) (Details) - USD ($)	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Percentage of company funded under ESOP	100.00%
Shares allocated under ESOP	108,696.645
Compensation expense related to the ESOP	$ 4,000,000	$ 4,000,000	$ 4,000,000
Measurement date	September 30
Number of employees under traditional defined benefit plan	54
Net loss amortized from accumulated other comprehensive income to net periodic benefit cost	$ 4,000,000
Amortization of estimated prior service credits	$ 3,000,000
Curtailments gain (loss)		(1,000,000)	2,000,000
Percentage of weighted-average target asset allocation in cash and other securities	5.00%
Net pension liability	$ 4,000,000	4,000,000
U.S. And Foreign Defined Contribution Plans [Member]
Defined contribution plans, expenses	$ 7,000,000	9,000,000	9,000,000
401 (K) [Member]
Participants contribution	75.00%
Participant's eligible compensation	$ 7.5
Maximum matching contribution	5.625%
U.S Plans [Member]
Weighted-average assumed health care cost trend rate	8.50%
Ultimate weighted-average health care cost trend rate	5.00%
Percentage of weighted-average target asset allocation in equity	65.00%
Percentage of weighted-average target asset allocation in fixed income	35.00%
Foreign Plans [Member]
Weighted-average assumed health care cost trend rate	8.00%
Ultimate weighted-average health care cost trend rate	6.00%
Percentage of weighted-average target asset allocation in equity	44.00%
Percentage of weighted-average target asset allocation in fixed income	51.00%
Supplemental Cash Balance Plan [Member]
Obligations under defined benefit plans	$ 6,000,000	4,000,000
U.S. Pension Benefits [Member]
Obligations under defined benefit plans	147,000,000	143,000,000	137,000,000
Foreign Pension Benefits [Member]
Obligations under defined benefit plans	236,000,000	241,000,000	228,000,000
U.S. Postretirement Benefits [Member]
Obligations under defined benefit plans	64,000,000	69,000,000	69,000,000
Accumulated benefit obligation	140,000,000	138,000,000
Foreign Postretirement Benefits [Member]
Obligations under defined benefit plans	15,000,000	15,000,000	$ 15,000,000
Accumulated benefit obligation	$ 218,000,000	$ 224,000,000
Minimum [Member]
Contribution percentage of total eligible pay	4.00%
Maximum [Member]
Contribution percentage of total eligible pay	8.00%
Curtailments gain (loss)	$ 1,000,000

Employee Benefit Plans (Change In Benefit Obligations And Change In Plan Assets) - USD ($)
$ in Millions

12 Months Ended

Sep. 30, 2011

Sep. 30, 2010

Sep. 30, 2009

$ 2

$ 1

U.S. Pension Benefits [Member]

300

143

137

$ 4

^[1]

(9)

(12)

147

143

137

104

103

104

(44)

(39)

Foreign Pension Benefits [Member]

^[2]

(44)

(39)

241

228

(2)

(9)

^[1]

(16)

(20)

(1)

236

241

228

197

193

(2)

197

193

(39)

(44)

U.S. Postretirement Benefits [Member]

^[2]

(39)

(44)

(1)

^[1]

(5)

(6)

(2)

(1)

(1)

(64)

(69)

Foreign Postretirement Benefits [Member]

^[2]

(64)

(69)

(1)

^[1]

(1)

(15)

^[2]

$ (15)

[1]	Included in this amount is $2 million and $1 million that the Company paid directly to the participants in its defined benefit plans in fiscal 2011 and 2010, respectively.
[2]	Included in this amount is $4 million of net pension liability as of September 30, 2011 and 2010 related to the Supermetals Business presented as Noncurrent Liabilities Held For Sale in the Consolidated Balance Sheets.

Employee Benefit Plans (Assumptions Used To Determine Benefit Obligations)	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
U.S. Pension Benefits [Member]
Discount rate	4.50%	4.50%	5.30%
Rate of increase in compensation	3.80%	3.80%	3.80%
Discount rate	4.50%	5.30%	7.50%
Expected long-term rate of return on plan assets	7.80%	7.80%	7.80%
Rate of increase in compensation	3.80%	3.80%	4.50%
Foreign Pension Benefits [Member]
Discount rate	4.80%	4.40%	5.00%
Rate of increase in compensation	3.10%	3.30%	3.40%
Discount rate	4.30%	5.00%	6.40%
Expected long-term rate of return on plan assets	6.10%	6.10%	6.50%
Rate of increase in compensation	3.30%	3.40%	3.80%
U.S. Postretirement Benefits [Member]
Discount rate	4.50%	4.50%	5.30%
Rate of increase in compensation	8.50%	7.50%	8.00%
Expected long-term rate of return on plan assets	4.50%	5.30%	7.50%
Rate of increase in compensation	7.50%	8.00%	8.00%
Foreign Postretirement Benefits [Member]
Discount rate	4.90%	4.80%	5.20%
Rate of increase in compensation	8.00%	8.00%	9.00%
Expected long-term rate of return on plan assets	4.80%	5.20%	7.10%
Rate of increase in compensation	8.00%	9.00%	9.00%

Employee Benefit Plans (Net Amounts Recognized In The Consolidated Balance Sheets) - USD ($) $ in Millions	Sep. 30, 2011	Sep. 30, 2010
Noncurrent liabilities	$ (161)	$ (160)
U.S. Pension Benefits [Member]
Noncurrent assets
Current liabilities		(1)
Noncurrent liabilities	(44)	(38)
Foreign Pension Benefits [Member]
Noncurrent assets	10	5
Current liabilities	(1)	(1)
Noncurrent liabilities	(48)	(48)
U.S. Postretirement Benefits [Member]
Noncurrent assets
Current liabilities	(6)	(6)
Noncurrent liabilities	(58)	(63)
Foreign Postretirement Benefits [Member]
Noncurrent assets
Noncurrent liabilities	$ (15)	$ (15)

Employee Benefit Plans (Amounts Recognized In Accumulated Other Comprehensive Income (Loss)) - USD ($) $ in Millions	Sep. 30, 2011	Sep. 30, 2010
U.S. Pension Benefits [Member]
Net actuarial loss	$ 34	$ 32
Net prior service cost (credit)	1	1
Balance in accumulated other comprehensive income, pretax	35	33
Foreign Pension Benefits [Member]
Net actuarial loss	52	54
Net prior service cost (credit)
Balance in accumulated other comprehensive income, pretax	52	54
U.S. Postretirement Benefits [Member]
Net actuarial loss	2	3
Net prior service cost (credit)	(14)	(16)
Balance in accumulated other comprehensive income, pretax	(12)	(13)
Foreign Postretirement Benefits [Member]
Net actuarial loss	2	3
Net prior service cost (credit)
Balance in accumulated other comprehensive income, pretax	$ 2	$ 3

Amount related to the pretax cost of benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as components of net periodic benefit cost.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph i
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 158
-Paragraph 7
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 106
-Paragraph 518
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 264
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (j)
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Prior Service Cost
-URI http://asc.fasb.org/extlink&oid=6521920
-Topic 715
-SubTopic 60

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Prior Service Cost
-URI http://asc.fasb.org/extlink&oid=6521884
-Topic 715
-SubTopic 30

Common stock, authorized shares | shares

Employee Benefit Plans (Estimated Future Benefit Payments) $ in Millions	Sep. 30, 2011 USD ($)
U.S. Pension Benefits [Member]
2012	$ 11
2013	10
2014	11
2015	11
2016	11
2017-2021	65
Foreign Pension Benefits [Member]
2012	12
2013	17
2014	13
2015	13
2016	15
2017-2021	83
U.S. Postretirement Benefits [Member]
2012	6
2013	6
2014	6
2015	6
2016	5
2017-2021	25
Foreign Postretirement Benefits [Member]
2012	1
2016	1
2017-2021	$ 5

Employee Benefit Plans (Net Periodic Defined Benefit Pension And Other Postretirement Benefit Costs) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
U.S. Pension Benefits [Member]
Service cost	$ 5	$ 5	$ 4
Interest cost	6	7	8
Expected return on plan assets	(8)	(9)	(9)
Amortization of prior service cost (credit)
Net losses (gains)			(1)
Settlements or curtailments cost (income)
Other
Net periodic benefit cost	3	3	2
Foreign Pension Benefits [Member]
Service cost	6	5	5
Interest cost	11	11	12
Expected return on plan assets	(13)	(11)	(12)
Amortization of prior service cost (credit)
Net losses (gains)	3	2	1
Settlements or curtailments cost (income)	(1)	1	(1)
Other	2
Net periodic benefit cost	9	8	5
U.S. Postretirement Benefits [Member]
Service cost	1	1	2
Interest cost	2	3	5
Expected return on plan assets
Amortization of prior service cost (credit)	(3)	(4)	(1)
Net losses (gains)
Settlements or curtailments cost (income)			(1)
Other
Net periodic benefit cost			5
Foreign Postretirement Benefits [Member]
Service cost
Interest cost	1	1	1
Expected return on plan assets
Amortization of prior service cost (credit)
Net losses (gains)
Settlements or curtailments cost (income)		(1)
Other
Net periodic benefit cost	$ 1	$ 1	$ 1

Employee Benefit Plans (Other Changes In Plan Assets And Benefit Obligations Recognized In Other Comprehensive Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
U.S. Pension Benefits [Member]
Net losses (gains)	$ 2	$ 5	$ 34
Prior service cost
Amortization of prior service (cost) credit
Amortization of prior unrecognized (loss) gain			1
Other
Total other comprehensive loss (income)	2	5	35
Foreign Pension Benefits [Member]
Net losses (gains)	1	12	18
Prior service cost			1
Amortization of prior unrecognized (loss) gain	(3)	(2)	(1)
Other		1
Total other comprehensive loss (income)	(2)	11	18
U.S. Postretirement Benefits [Member]
Net losses (gains)	(1)	1	11
Prior service cost	(2)		(17)
Amortization of prior service (cost) credit	4	4	2
Total other comprehensive loss (income)	1	5	(4)
Foreign Postretirement Benefits [Member]
Net losses (gains)	(1)		2
Prior service cost
Amortization of prior service (cost) credit
Amortization of prior unrecognized (loss) gain
Other
Total other comprehensive loss (income)	$ (1)		$ 2

Employee Benefit Plans (Sensitivity Analysis) $ in Millions	12 Months Ended
Employee Benefit Plans (Sensitivity Analysis) $ in Millions	Sep. 30, 2011 USD ($)
U.S. Postretirement Benefits [Member]
1 -Percent-Point Increase, Effect on postretirement benefit obligation
1 -Percent-Point Decrease, Effect on postretirement benefit obligation
Foreign Postretirement Benefits [Member]
1 -Percent-Point Increase, Effect on postretirement benefit obligation	2
1 -Percent-Point Decrease, Effect on postretirement benefit obligation	$ (2)

Employee Benefit Plans (Defined Benefit Pension Plans Weighted Average Asset Allocations)	Sep. 30, 2011	Sep. 30, 2010
U.S. Pension Benefits [Member]
Equity securities	57.00%	64.00%
Debt securities	43.00%	36.00%
Total	100.00%	100.00%
Foreign Pension Benefits [Member]
Equity securities	44.00%	44.00%
Debt securities	50.00%	51.00%
Cash and other securities	6.00%	5.00%
Total	100.00%	100.00%

Stock-Based Compensation (Narrative) (Details)
$ / shares in Units, $ in Millions

12 Months Ended

Sep. 30, 2011

USD ($)

$ / shares

Sep. 30, 2010

USD ($)

$ / shares

Sep. 30, 2009

USD ($)

$ / shares

6,400,000

Percentage of vesting in first anniversary

30.00%

Percentage of vesting in second anniversary

30.00%

Percentage of vesting in third anniversary

40.00%

Incremental stock-based compensation expense

$ 4

Net stock-based compensation expense

$ 10

$ 11

$ 12

Outstanding loan balances

$ 2

$ 8

Closing common stock price | $ / shares

$ 24.78

Options exercised | shares

180,000

Options vested

612,000

441,000

79,000

Estimated weighted average grant date fair values of options granted | $ / shares

$ 12.09

Stock Options [Member]

Percentage of exercise price equal to market price on the date of grant

100.00%

Vesting period (in years)

three

Expiration period, years

ten

five

Intrinsic value of options exercised

$ 3

$ 1

$ 0

Cash received from exercises

Total fair value of the options vested

$ 3

$ 2

$ 1

Estimated weighted average grant date fair values of options granted | $ / shares

$ 12.09

$ 7.41

$ 3.98

Restricted Stock [Member]

Vesting period (in years)

three

Percentage of market price

30.00%

Estimated weighted average grant date fair value | $ / shares

$ 9.56

Awards granted | shares

Intrinsic value of restricted stock units vested

$ 27

$ 11

$ 5

Restricted Stock Units (RSUs) [Member]

Vesting period (in years)

three

Estimated weighted average grant date fair value | $ / shares

$ 34.76

$ 24.49

Awards granted | shares

^[1]

387,000

Intrinsic value of restricted stock units vested

$ 0

Non-Vested Restricted Stock Units [Member]

Unrecognized compensation cost related to non-vested

$ 14

Weighted-average period, years

1.6

Non-Vested Options [Member]

Unrecognized compensation cost related to non-vested

$ 2

Weighted-average period, years

0.8

Non-Vested Restricted Stock [Member]

Weighted-average period, years

0.4

Supplemental Retirement Savings Plan [Member]

Supplemental retirement savings plan, aggregate value of the accounts, shares | shares

125,000

166,000

Supplemental retirement savings plan aggregate value of the accounts paid in cash

$ 1

Maximum [Member] | Restricted Stock Units (RSUs) [Member]

Intrinsic value of restricted stock units vested

Maximum [Member] | Non-Vested Restricted Stock [Member]

Unrecognized compensation cost related to non-vested

$ 1

[1]

Stock-Based Compensation (Stock-Based Compensation Expenses) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Stock-based compensation expense before tax	$ 15	$ 18	$ 19
Income tax benefit	(5)	(7)	(7)
Net stock-based compensation expense	10	11	12
Cost Of Sales [Member]
Stock-based compensation expense before tax	5	6	7
Selling And Administrative Expenses [Member]
Stock-based compensation expense before tax	9	11	11
Research And Technical Expenses [Member]
Stock-based compensation expense before tax	$ 1	$ 1	$ 1

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Stock Options, Total Options, Outstanding at September 30, 2010 | shares

Stock-Based Compensation (Equity Incentive Plan Activity) (Details)

12 Months Ended

Sep. 30, 2011

$ / shares

Sep. 30, 2010

$ / shares

Sep. 30, 2009

$ / shares

1,765,000

Stock Options, Total Options, Granted | shares

250,000

Stock Options, Total Options, Exercised / Vested | shares

(180,000)

Stock Options, Total Options, Cancelled / Forfeited | shares

(63,000)

Stock Options, Total Options, Outstanding at September 30, 2011 | shares

1,772,000

1,765,000

Stock Options, Total Options, Exercisable at September 30, 2011 | shares

809,000

Stock Options, Total Options, Expected to vest | shares

^[1]

940,000

Stock Options, Weighted Average Exercise Price, Outstanding at September 30, 2010

$ 20.40

Stock Options, Weighted Average Exercise Price, Granted

34.64

Stock Options, Weighted Average Exercise Price, Exercised / Vested

23.32

Stock Options, Weighted Average Exercise Price, Cancelled / Forfeited

24.74

Stock Options, Weighted Average Exercise Price, Outstanding at September 30, 2011

21.96

$ 20.40

Stock Options, Weighted Average Exercise Price, Exercisable at September 30, 2011

$ 20.70

Stock Options, Weighted Average Exercise Price, Expected to vest

^[1]

23.07

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageGrantDateFairValue

$ 6.06

5.21

Stock Options, Weighted Average Grant Date Fair Value, Granted

$ 12.09

Stock Options, Weighted Average Grant Date Fair Value, Exercised / Vested

5.67

Stock Options, Weighted Average Grant Date Fair Value, Cancelled / Forfeited

$ 7.35

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageGrantDateFairValue

$ 6.06

5.21

Stock options expected to vest in the future, net of estimated forfeitures, weighted average remaining contractual life, in years

8.1

Stock Options [Member]

Stock Options, Weighted Average Grant Date Fair Value, Granted

$ 12.09

$ 7.41

$ 3.98

Restricted Stock [Member]

Restricted Stock / Units, Outstanding at September 30, 2010 | shares

829,000

Restricted Stock / Units, Granted | shares

Restricted Stock / Units, Exercised / Vested | shares

(820,000)

Restricted Stock / Units, Cancelled / Forfeited | shares

(6,000)

Restricted Stock / Units, Outstanding at September 30, 2011 | shares

3,000

829,000

Restricted Stock / Units, Weighted Average Grant Date Fair Value, Outstanding at September 30, 2010

$ 20.81

Restricted Stock / Units, Weighted Average Grant Date Fair Value, Granted

$ 9.56

Restricted Stock / Units, Weighted Average Grant Date Fair Value, Exercised / Vested

22.61

Restricted Stock / Units, Weighted Average Grant Date Fair Value, Cancelled / Forfeited

22.43

Restricted Stock / Units, Weighted Average Grant Date Fair Value, Outstanding at September 30, 2011

$ 9.56

$ 20.81

Restricted Stock Units (RSUs) [Member]

Restricted Stock / Units, Outstanding at September 30, 2010 | shares

^[2]

454,000

Restricted Stock / Units, Granted | shares

^[2]

387,000

Restricted Stock / Units, Performance-based adjustment | shares

^[2],[3]

58,000

Restricted Stock / Units, Exercised / Vested | shares

^[2]

(4,000)

Restricted Stock / Units, Cancelled / Forfeited | shares

^[2]

(29,000)

Restricted Stock / Units, Outstanding at September 30, 2011 | shares

^[2]

866,000

454,000

Restricted Stock / Units, Weighted Average Grant Date Fair Value, Outstanding at September 30, 2010

$ 23.90

Restricted Stock / Units, Weighted Average Grant Date Fair Value, Granted

$ 34.76

$ 24.49

Restricted Stock / Units, Weighted Average Grant Date Fair Value, Performance-based adjustment | shares

^[3]

28.60

Restricted Stock / Units, Weighted Average Grant Date Fair Value, Exercised / Vested

$ 28.63

Restricted Stock / Units, Weighted Average Grant Date Fair Value, Cancelled / Forfeited

28.48

Restricted Stock / Units, Weighted Average Grant Date Fair Value, Outstanding at September 30, 2011

$ 28.89

$ 23.90

[1]	Stock options expected to vest in the future, net of estimated forfeitures, have a weighted average remaining contractual life of 8.1 years.
[2]	The number "Granted" represents the number of shares issuable upon vesting of time-based restricted stock units and performance-based restricted stock units, assuming the Company performs at the target performance level in each year of the three-year performance period. Restricted stock units outstanding as of September 30, 2010 have been recast to include the incremental number of shares issuable upon vesting of outstanding performance-based restricted stock units, based on the Company achieving performance at a level greater than target under the 2010 performance targets.
[3]	Represents the incremental number of shares issuable upon vesting of outstanding performance-based restricted stock units, based on the Company achieving performance at a level greater than target under the 2011 performance targets.

Stock-Based Compensation (Stock Options Outstanding And Vested Options) (Details) $ in Millions	12 Months Ended
	Sep. 30, 2011 USD ($)
Stock Based Compensation
Total Options Outstanding, Aggregate Intrinsic Value	$ 5
Total Options Outstanding, Weighted Average Remaining Contractual Term (in years)	7.5
Exercisable Options, Aggregate Intrinsic Value	$ 3
Exercisable Options, Weighted Average Remaining Contractual Term (in years)	6.7

Stock-Based Compensation (Weighted-Average Assumptions) (Details)	12 Months Ended
	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Sep. 30, 2009 USD ($)
Stock Based Compensation
Expected stock price volatility	43.00%	42.00%	39.00%
Risk free interest rate	1.80%	2.80%	0.40%
Expected life of options (years)	6	6	6
Expected annual dividends per year	$ 0.72	$ 0.72	$ 0.72

Restructuring (Narrative) (Details) $ in Millions	1 Months Ended	12 Months Ended
Restructuring (Narrative) (Details) $ in Millions	Feb. 28, 2011	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Sep. 30, 2009 USD ($)	Sep. 30, 2013 USD ($)	Sep. 30, 2012 USD ($)
Severance costs		$ 5
Restructuring costs in accrued expenses		11	$ 19	$ 21
Gain on assets sales		1
Cash receipts on assets sales		1
Closure Of Grigno [Member]
Affected employees	37
Restructuring accelerated depreciation and asset impairments		3
Restructuring charges		6
Severance costs		3
Expected severance-related restructuring charges payment					$ 1	$ 4
Cash payments		1
Expected cash outlays beyond fiscal year		2
Restructuring costs in accrued expenses		2
Closure Of Thane [Member]
Affected employees			120
Pre-tax charge to earnings		20
Restructuring accelerated depreciation and asset impairments		10
Restructuring charges		19
Severance costs		7
Expected cash outlays		7
Cash payments		7
Expected cash outlays beyond fiscal year		1
Restructuring costs in accrued expenses		1
Closure Of Thane [Member] \| Demolition And Site Clearing Costs [Member]
Restructuring charges		1
Closure Of Thane [Member] \| Other Post Closing Costs [Member]
Restructuring charges		$ 2
2009 Global Restructuring [Member]
Affected employees		400
Number of facilities closed				3
Pre-tax charge to earnings		$ 120
Restructuring accelerated depreciation and asset impairments		45
Severance costs		54
Expected cash outlays		68
Cash payments		68
Expected cash outlays remainder fiscal year		3
Restructuring costs in accrued expenses		3
2009 Global Restructuring [Member] \| Demolition And Site Clearing Costs [Member]
Restructuring charges		6
2009 Global Restructuring [Member] \| Other Post Closing Costs [Member]
Restructuring charges		$ 15

Restructuring (Recorded Restructuring Activities) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Restructuring reserve, period expense	$ 18	$ 46	$ 87
Cost Of Sales [Member]
Restructuring reserve, period expense	16	36	80
Selling And Administrative Expenses [Member]
Restructuring reserve, period expense	$ 2	$ 10	5
Research And Technical Expenses [Member]
Restructuring reserve, period expense			$ 2

Restructuring (Restructuring Activities And Related Reserves) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Reserve at beginning of period	$ 19	$ 21
Charges	18	46	$ 87
Costs charged against assets and other	(6)	(11)
Proceeds from sale	6	3
Cash paid	(26)	(36)
Foreign currency translation adjustment		(4)
Reserve at end of period	11	19	21
Severance And Employee Benefits [Member]
Reserve at beginning of period	18	20
Charges	8	29
Costs charged against assets and other	1
Proceeds from sale
Cash paid	(17)	(27)
Foreign currency translation adjustment	(1)	(4)
Reserve at end of period	9	18	20
Environmental Remediation [Member]
Reserve at beginning of period	1	1
Charges	3	2
Costs charged against assets and other
Proceeds from sale
Cash paid	(4)	(2)
Foreign currency translation adjustment
Reserve at end of period		1	1
Asset Impairment And Accelerated Depreciation [Member]
Reserve at beginning of period
Charges	3	11
Costs charged against assets and other	(3)	(11)
Proceeds from sale
Cash paid
Foreign currency translation adjustment
Reserve at end of period
Asset Sales [Member]
Reserve at beginning of period
Charges	(1)	(3)
Costs charged against assets and other	(4)
Proceeds from sale	6	3
Cash paid	(1)
Foreign currency translation adjustment
Reserve at end of period
Other [Member]
Reserve at beginning of period
Charges	5	7
Costs charged against assets and other
Proceeds from sale
Cash paid	(4)	(7)
Foreign currency translation adjustment	1
Reserve at end of period	$ 2

Stockholders' Equity (Narrative) (Details) - USD ($)	12 Months Ended
Stockholders' Equity (Narrative) (Details) - USD ($)	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009	Sep. 30, 2007
Stockholders' Equity
Repurchase authorization, shares	1,600,000	0	3,500	10,000,000
Shares remaining available for repurchase under the current authorization	2,700,000
Cash dividends paid	$ 0.72	$ 0.72	$ 0.72

Stockholders' Equity (Schedule Of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	Sep. 30, 2011	Sep. 30, 2010
Stockholders' Equity
Foreign currency translation adjustments	$ 163	$ 144
Unrealized holding gain on investments	1	1
Change in funded status of retirement plans	(58)	(57)
Accumulated other comprehensive income	$ 106	$ 88

The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 26
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph i
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 158
-Paragraph 7
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e637-108580

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e681-108580

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e653-108580

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

Net income (loss) attributable to Cabot Corporation

Earnings Per Share (Components Of Basic And Diluted Earnings Per Common Share) (Details) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions

3 Months Ended

12 Months Ended

Sep. 30, 2011

Jun. 30, 2011

Mar. 31, 2011

Dec. 31, 2010

Sep. 30, 2010

Jun. 30, 2010

Mar. 31, 2010

Dec. 31, 2009

Sep. 30, 2011

Sep. 30, 2010

Sep. 30, 2009

Basic EPS:

$ 50

$ 60

$ 51

$ 75

$ 35

$ 47

$ 43

$ 29

$ 236

$ 154

$ (77)

Less: Dividends and dividend equivalents to participating securities

Less: Undistributed earnings allocated to participating securities

^[1]

Earnings (loss) allocated to common shareholders (numerator)

$ 233

$ 151

$ (79)

Weighted average common shares and participating securities outstanding

65.4

65.3

Less: Participating securities

^[1]

0.8

1.5

2.5

Adjusted weighted average common shares (denominator)

64.6

63.8

62.8

Income (loss) from continuing operations attributable to Cabot Corporation

$ 2.80

$ 1.96

$ (1.21)

Income (loss) from discontinued operations

0.82

0.41

(0.04)

Net income (loss) attributable to Cabot Corporation

$ 3.62

$ 2.37

$ (1.25)

Diluted EPS:

Earnings (loss) allocated to common shareholders

$ 233

$ 151

$ (79)

Plus: Earnings allocated to participating securities

Less: Adjusted earnings allocated to participating securities

^[2]

(3)

(2)

Earnings (loss) available to common shares (numerator)

$ 233

$ 151

$ (79)

Adjusted weighted average common shares outstanding

64.6

63.8

62.8

Common shares issuable

^[3]

0.8

0.5

Adjusted weighted average shares (denominator)

65.4

64.3

62.8

Income (loss) from continuing operations attributable to Cabot Corporation

$ 0.64

$ 0.73

$ 0.52

$ 0.88

$ 0.42

$ 0.57

$ 0.59

$ 0.36

$ 2.77

$ 1.94

$ (1.21)

Income (Loss) from discontinued operations - diluted

0.12

0.19

0.24

0.25

0.12

0.15

0.06

0.08

0.80

0.41

(0.04)

Net income (loss) attributable to Cabot Corporation

$ 0.76

$ 0.92

$ 0.76

$ 1.13

$ 0.54

$ 0.72

$ 0.65

$ 0.44

$ 3.57

$ 2.35

$ (1.25)

[1]

(1) Participating securities consist of shares of unvested restricted stock, vested restricted stock awards held by employees in which Cabot has a security interest, and unvested time-based restricted stock units. Undistributed earnings are the earnings which remain after dividends declared during the period are assumed to be distributed to the common and participating shareholders. Undistributed earnings are allocated to common and participating shareholders on the same basis as dividend distributions. The calculation of undistributed earnings is as follows:


	YearsEndedSeptember30
	2011		2010		2009
	(Dollars in millions)
Calculation of undistributed earnings:
Net income (loss) attributable to Cabot Corporation	$	236	$	154	$	(77	)
Less: Dividends declared on common stock		46		46		46
Less: Dividends and dividend equivalents to participating securities		1		1		2

Undistributed earnings	$	189	$	107	$	(125	)

Allocation of undistributed earnings:
Undistributed earnings allocated to common shareholders	$	187	$	105	$	(125	)
Undistributed earnings allocated to participating securities		2		2

Undistributed earnings	$	189	$	107	$	(125	)

[2]

(2) Undistributed earnings are adjusted for the assumed distribution of dividends to the dilutive securities, which are described in (3) below, and then reallocated to participating securities.

[3]

(3) Represents incremental shares of common stock from the (i) assumed exercise of stock options issued under Cabot's equity incentive plans; (ii) assumed issuance of shares to employees pursuant to the Company's Supplemental Retirement Savings Plan; and (iii) assumed issuance of shares for outstanding and achieved performance-based stock unit awards issued under Cabot's equity incentive plans using the treasury stock method. For fiscal 2011, 253,000 incremental shares of common stock were not included in the calculation of diluted earnings per share because the inclusion of these shares would have been antidilutive. For fiscal 2010, 193,000 incremental shares of common stock were not included in the calculation of diluted earnings per share because those shares' exercise prices were greater than the average market price of Cabot common stock for that period. For fiscal 2009, 3,833,000 incremental shares of common stock were excluded from the calculation of diluted earnings per share as those shares would have been antidilutive due to the Company's net loss position.

Earnings Per Share (Calculation Of Undistributed Earnings) (Details) - USD ($)
$ in Millions

3 Months Ended

12 Months Ended

Sep. 30, 2011

Jun. 30, 2011

Mar. 31, 2011

Dec. 31, 2010

Sep. 30, 2010

Jun. 30, 2010

Mar. 31, 2010

Dec. 31, 2009

Sep. 30, 2011

Sep. 30, 2010

Sep. 30, 2009

Earnings Per Share

Net income (loss) attributable to Cabot Corporation

$ 50

$ 60

$ 51

$ 75

$ 35

$ 47

$ 43

$ 29

$ 236

$ 154

$ (77)

Less: Dividends declared on common stock

Less: Dividends and dividend equivalents to participating securities

Undistributed earnings allocated to common shareholders

187

105

(125)

Undistributed earnings allocated to participating securities

^[1]

Undistributed earnings

$ 189

$ 107

$ (125)

Shares excluded from calculation of EPS

253,000

193,000

3,833,000

[1]


	YearsEndedSeptember30
	2011		2010		2009
	(Dollars in millions)
Calculation of undistributed earnings:
Net income (loss) attributable to Cabot Corporation	$	236	$	154	$	(77	)
Less: Dividends declared on common stock		46		46		46
Less: Dividends and dividend equivalents to participating securities		1		1		2

Undistributed earnings	$	189	$	107	$	(125	)

Allocation of undistributed earnings:
Undistributed earnings allocated to common shareholders	$	187	$	105	$	(125	)
Undistributed earnings allocated to participating securities		2		2

Undistributed earnings	$	189	$	107	$	(125	)

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 13, 14
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 171
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 40
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Diluted Earnings Per Share
-URI http://asc.fasb.org/extlink&oid=6510752

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Contingent Stock Agreement
-URI http://asc.fasb.org/extlink&oid=6508534

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 07-4
-Paragraph 4
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 87-21
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph a
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 10, 15
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28, 29, 30
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 5
-Section 03
-Paragraph 19

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 20
-Article 9

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Net Income
-URI http://asc.fasb.org/extlink&oid=6518256

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=6519514

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.18)
-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.19)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e565-108580

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.22)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 16: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A7
-Appendix A

Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended			36 Months Ended
Income Taxes (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009	Sep. 30, 2011	Sep. 30, 2008
Net tax settlements and investment incentive tax credits	$ 38	$ 17	$ 12	$ 38
Tax settlements	14			14
Tax Benefits from repatriation of high taxed income	24			24
Other tax credit carryforwards	137			137
Net tax charge for other miscellaneous items		1
Net operating loss carryforwards	565			565
Net deferred tax assets	282			282
Tax credits	86			131
Required future taxable operating income	$ 706
Expected term to realize deferred tax asset, years	20
Operating loss carry forward	$ 35			35
Future taxable operating income	117
Increased/(decreased) valuation allowance	12	6	33
Unrecognized tax benefits	65	75	81	65	$ 80
Unrecognized tax benefits, recorded	39			39
Unrecognized tax benefits, not recorded	26			26
Accruals for penalties	3			3
Accruals for interest	14			14
Favorable impact on tax provision	56
Favorable impact of unrecognized tax benefits	13
Total penalties and interest	3	$ 3	$ 3
Non U.S. Subsidiaries [Member]
Undistributed earnings	887			887
U.S. Management [Member]
Net deferred tax assets	$ 247			$ 247

Income Taxes (Income (Loss) Before Income Taxes) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Income Taxes
Domestic									$ (25)	$ 3	$ (72)
Foreign									228	163	(27)
Income (loss) from continuing operations before income taxes and equity in net earnings of affiliated companies	$ 47	$ 62	$ 48	$ 46	$ 39	$ 54	$ 40	$ 33	$ 203	$ 166	$ (99)

Income Taxes (Provision (Benefit) On Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Income Taxes
U.S. federal and state, Current									$ (7)	$ (8)	$ (2)
U.S. federal and state, Deferred									(51)	(14)	(32)
U.S. federal and state, Total									(58)	(22)	(34)
Foreign Current									57	51	27
Foreign Deferred									7	1	(14)
Foreign, Total									64	52	13
Total U.S and foreign	$ 2	$ 10	$ 9	$ (15)	$ 11	$ 14	$ (3)	$ 8	$ 6	$ 30	$ (21)

The component of total income tax expense for the period comprised of the increase (decrease) in the entity's net foreign deferred tax assets and liabilities attributable to continuing operations as determined by applying the provisions of applicable enacted tax laws of countries other than the country of domicile.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 45
-Subparagraph b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.7)
-URI http://asc.fasb.org/extlink&oid=6889476&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Deferred Tax Expense (or Benefit)
-URI http://asc.fasb.org/extlink&oid=6510177

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 289
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section I
-Subsection 7

Income Taxes (Reconciliation Using U.S. Statutory Rate (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Income Taxes
Computed tax expense at the federal statutory rate									$ 70	$ 58	$ (35)
Impact of taxation at different rates, repatriation and other									(29)	(26)	(3)
Impact of repatriation of high tax income									(24)
Impact of investment incentive credits									(2)	(2)	(1)
Impact of foreign losses for which a current tax benefit is not available									6	17	30
State taxes, net of federal effect
U.S. and state benefits from research and experimentation activities									(3)	(1)	(4)
Tax audit settlements									(12)	(15)	(9)
Other, net										(1)	1
Total U.S and foreign	$ 2	$ 10	$ 9	$ (15)	$ 11	$ 14	$ (3)	$ 8	$ 6	$ 30	$ (21)

Income Taxes (Components Of Deferred Income Taxes) (Details) - USD ($) $ in Millions	Sep. 30, 2011	Sep. 30, 2010
Income Taxes
Depreciation and amortization	$ 73	$ 67
Pension and other benefits	87	89
Environmental liabilities	3	3
Inventory	12	16
Deferred expenses	11	15
Net operating loss carry-forwards	125	131
Other tax carry-forwards	137	95
Deferred tax assets, Other	28	26
Subtotal	476	442
Valuation allowances	(138)	(126)
Total deferred tax assets	338	316
Depreciation and amortization	28	28
Pension and other benefits	2	4
Unremitted earnings of non-U.S. subsidiaries	18	12
Inventory	3	3
Other	5	6
Total deferred tax liabilities	$ 56	$ 53

Income Taxes (Expiration Dates Of Carryforwards) (Details) $ in Millions	12 Months Ended
	Sep. 30, 2011 USD ($)
NOLs	$ 565
Other Credits	$ 137
Expiration periods	<font style="font-family: Times New Roman;" class="_mt" size="2">2019 </font>
2012 To 2018 [Member]
NOLs	$ 132
Other Credits	6
2019 And Thereafter [Member]
NOLs	131
Other Credits	110
Indefinite Carryforward [Member]
NOLs	302
Other Credits	$ 21
Minimum [Member]
Expiration periods	<font style="font-family: Times New Roman;" class="_mt" size="2">2012 </font>
Maximum [Member]
Expiration periods	2018

Income Taxes (Reconciliation Of Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Income Taxes
Balance at beginning of the year	$ 75	$ 81	$ 80
Additions based on tax positions related to the current year	2	6	7
Additions based on tax positions of prior years	1	3	4
Reduction for tax positions of prior years	(13)	(15)	(10)
Balance at end of the year	$ 65	$ 75	$ 81

Commitments And Contingencies (Narrative) (Details)	12 Months Ended
Commitments And Contingencies (Narrative) (Details)	Sep. 30, 2011 USD ($) years	Sep. 30, 2010 USD ($)	Sep. 30, 2009 USD ($)	Sep. 30, 2008 USD ($)
Lease expiration period, years \| years	10
Rent expense under such operating lease agreement	$ 19,000,000	$ 21,000,000	$ 27,000,000
Aggregate self-insured liability	6,000,000
Retention for medical costs per person per annum	200,000
Interest expense	39,000,000	40,000,000	30,000,000
Benefit From Legal Judgment	3,000,000
Non-Controlling Interests [Member]
Raw materials purchases	134,000,000	126,000,000	57,000,000
Accounts payable and accrued liabilities	10,000,000	10,000,000
Environmental Matters [Member]
Reserve for environmental matters	6,000,000	7,000,000
Reserve for environmental matters included in accrued expenses	2,000,000	2,000,000
Reserve for environmental matters included in other liabilities	4,000,000	5,000,000
Charges for environmental expense	1,000,000	3,000,000
Cash payments for environmental reserves	$ 2,000,000	$ 1,000,000	3,000,000
Weighted average risk free rate for environmental liability	2.00%
Environmental Matters [Member] \| Operating And Maintenance Component [Member]
Reserve for environmental matters	$ 3,000,000
Expected future payments, 2012	1,000,000
Expected future payments, 2013	1,000,000
Expected future payments, 2014	1,000,000
Expected future payments, 2015	1,000,000
Expected future payments, thereafter	$ 1,000,000
Respirator Liabilities [Member]
Number of claimants	42,000	45,000
Annual fees paid by transferee to transferor company	$ 400,000
Respirator reserve on discounted basis		$ 11,000,000
Respirator reserve on undiscounted basis		16,000,000
Discount rate	5.30%
Expected aggregate undiscounted amount of future payments, fiscal 2011	$ 2,000,000
Expected aggregate undiscounted amount of future payments, fiscal 2012	1,000,000
Expected aggregate undiscounted amount of future payments, fiscal 2013	1,000,000
Expected aggregate undiscounted amount of future payments, fiscal 2014	1,000,000
Expected aggregate undiscounted amount of future payments, fiscal 2015	1,000,000
Expected aggregate undiscounted amount of future payments, fiscal 2016 through 2062	10,000,000
Cash payments for respirator reserves		5,000,000	2,000,000	$ 2,000,000
Feedstock Pipeline Breakage [Member]
Benefit From Legal Judgment	9,000,000
Maximum [Member] \| Environmental Matters [Member]
Charges for environmental expense			1,000,000
Interest expense	1,000,000	$ 1,000,000	$ 1,000,000
Maximum [Member] \| Respirator Liabilities [Member]
Interest expense	$ 1,000,000

Commitments And Contingencies (Schedule Of Future Minimum Rental Commitments Under Non-cancelable Leases) (Details) $ in Millions	Sep. 30, 2011 USD ($)
Commitments And Contingencies
2012	$ 19
2013	15
2014	12
2015	11
2016	8
2017 and thereafter	29
Total future minimum rental commitments	$ 94

Commitments And Contingencies (Schedule Of Raw Material Purchased Under Long Term Purchase Agreements) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Raw material purchased	$ 358	$ 336	$ 222
Core Segment [Member]
Raw material purchased	340	294	136
Performance Segment [Member]
Raw material purchased	$ 18	36	82
Specialty Fluids Segment [Member]
Raw material purchased		$ 6	$ 4

Commitments And Contingencies (Schedule Of Other Long-Term Commitments) (Details) $ in Millions	Sep. 30, 2011 USD ($)
Payments Due by Fiscal Year 2012	$ 289
Payments Due by Fiscal Year 2013	276
Payments Due by Fiscal Year 2014	260
Payments Due by Fiscal Year 2015	257
Payments Due by Fiscal Year 2016	371
Payments Due Thereafter	2,838
Payments Due, Total	4,291
Core Segment [Member]
Payments Due by Fiscal Year 2012	272
Payments Due by Fiscal Year 2013	245
Payments Due by Fiscal Year 2014	229
Payments Due by Fiscal Year 2015	227
Payments Due by Fiscal Year 2016	200
Payments Due Thereafter	2,705
Payments Due, Total	3,878
Performance Segment [Member]
Payments Due by Fiscal Year 2012	16
Payments Due by Fiscal Year 2013	30
Payments Due by Fiscal Year 2014	31
Payments Due by Fiscal Year 2015	30
Payments Due by Fiscal Year 2016	171
Payments Due Thereafter	133
Payments Due, Total	411
New Business Segment [Member]
Payments Due by Fiscal Year 2012	1
Payments Due by Fiscal Year 2013	1
Payments Due, Total	$ 2

Concentration Of Credit Risk (Narrative) (Details)	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Goodyear Tire And Rubber Company [Member]
Net sales percentage		12.00%	11.00%
No Customer Of Concentration Risk [Member]
Concentration of risk percentage	10.00%

Concentration Of Credit Risk (Schedule Of Account Receivable) (Details) - USD ($) $ in Millions	Sep. 30, 2011	Sep. 30, 2010
Tire Manufacturers [Member]
Accounts receivable	$ 318	$ 259

Financial Information By Segment & Geographic Area (Schedule Of Performance Segment) (Details) - USD ($)
$ in Millions

12 Months Ended

Sep. 30, 2011

Sep. 30, 2010

Sep. 30, 2009

Performance Segment [Member]

^[1]

$ 3,102

$ 2,716

$ 2,108

Performance Segment [Member] | Performance Products Business [Member]

880

783

620

Performance Segment [Member] | Fumed Metal Oxides Business [Member]

626

531

410

$ 254

$ 252

$ 210

[1]	Unallocated and other reflects royalties paid by equity affiliates, external shipping and handling fees, and the impact of the corporate adjustment for unearned revenue.

Financial Information By Segment & Geographic Area (Schedule Of New Business Segment) (Details) - USD ($)
$ in Millions

12 Months Ended

Sep. 30, 2011

Sep. 30, 2010

Sep. 30, 2009

New Business Segment [Member]

^[1]

$ 3,102

$ 2,716

$ 2,108

New Business Segment [Member] | Inkjet Colorants Business [Member]

117

105

New Business Segment [Member] | Aerogel Business [Member]

New Business Segment [Member] | Cabot Superior MicroPowders Business [Member]

New Business Segment [Member] | Cabot Elastomer Composites Business [Member]

$ 17

$ 5

[1]	Unallocated and other reflects royalties paid by equity affiliates, external shipping and handling fees, and the impact of the corporate adjustment for unearned revenue.

Financial Information By Segment & Geographic Area (Financial Information By Segment) (Details) - USD ($)
$ in Millions

3 Months Ended

12 Months Ended

Sep. 30, 2011

Jun. 30, 2011

Mar. 31, 2011

Dec. 31, 2010

Sep. 30, 2010

Jun. 30, 2010

Mar. 31, 2010

Dec. 31, 2009

Sep. 30, 2011

Sep. 30, 2010

Sep. 30, 2009

^[1]

$ 3,102

$ 2,716

$ 2,108

139

137

164

Income (loss) from continuing operations before taxes

$ 2

$ 1

$ 3

$ 2

$ 1

$ 3

^[2]

^[3]

203

166

(99)

^[4]

3,141

2,886

3,141

2,886

2,676

Total expenditures for additions to long-lived assets

^[5]

241

107

110

Core Segment [Member]

^[1]

1,952

1,660

1,283

Income (loss) from continuing operations before taxes

^[3]

183

139

^[4]

1,509

1,277

1,509

1,277

1,215

Total expenditures for additions to long-lived assets

^[5]

126

Performance Segment [Member]

^[1]

880

783

620

Income (loss) from continuing operations before taxes

^[3]

140

125

^[4]

661

544

661

544

507

Total expenditures for additions to long-lived assets

^[5]

New Business Segment [Member]

^[1]

117

105

Income (loss) from continuing operations before taxes

^[3]

(3)

^[4]

Total expenditures for additions to long-lived assets

^[5]

Specialty Fluids Segment [Member]

^[1]

Income (loss) from continuing operations before taxes

^[3]

^[4]

101

Total expenditures for additions to long-lived assets

^[5]

Segment Total [Member]

^[1]

3,018

2,629

2,037

131

121

158

Income (loss) from continuing operations before taxes

^[3]

354

314

^[4]

2,361

2,009

2,361

2,009

1,893

Total expenditures for additions to long-lived assets

^[5]

235

104

109

Unallocated And Other [Member]

^[1],[3],[6]

^[3],[6]

Income (loss) from continuing operations before taxes

^[3],[6]

^[3],[6]

(151)

(148)

(160)

^[3],[4],[6]

780

877

780

877

783

Total expenditures for additions to long-lived assets

^[3],[6]

^[3],[5],[6]

$ 6

$ 3

$ 1

[1]	Unallocated and other reflects royalties paid by equity affiliates, external shipping and handling fees, and the impact of the corporate adjustment for unearned revenue.
[2]	Equity in net income of affiliated companies is included in segment EBIT and is removed from Unallocated and other to reconcile to income (loss) from operations before taxes.
[3]	Income (loss) from continuing operations before taxes for Unallocated and Other includes:
[4]	Unallocated and Other assets includes cash, marketable securities, cost investments, income taxes receivable, deferred taxes, headquarters' assets, and Current and Non-current assets held for sale.
[5]	Expenditures for additions to long-lived assets include total equity and other investments, property, plant and equipment, intangible assets and assets held for rent.
[6]	Unallocated and other includes certain items and eliminations that are not allocated to the operating segments. Management does not consider these items necessary for an understanding of the operating results of these segments and such amounts are excluded in the segment reporting to the Chief Operating Decision Maker.

Financial Information By Segment & Geographic Area (Royalties Paid By Equity Affiliates And External Shipping And Handling Fees) (Details) - USD ($)
$ in Millions

12 Months Ended

Sep. 30, 2011

Sep. 30, 2010

Sep. 30, 2009

Unallocated And Other [Member]

^[1]

$ 3,102

$ 2,716

$ 2,108

Royalties paid by equity affiliates and other operating revenues

(2)

Shipping and handling fees

^[1],[2],[3]

$ 84

$ 87

$ 71

[1]	Unallocated and other reflects royalties paid by equity affiliates, external shipping and handling fees, and the impact of the corporate adjustment for unearned revenue.
[2]	Income (loss) from continuing operations before taxes for Unallocated and Other includes:
[3]	Unallocated and other includes certain items and eliminations that are not allocated to the operating segments. Management does not consider these items necessary for an understanding of the operating results of these segments and such amounts are excluded in the segment reporting to the Chief Operating Decision Maker.

Financial Information By Segment & Geographic Area (Schedule Of Income (Loss) Before Taxes For Unallocated And Other) (Details) - USD ($)
$ in Millions

3 Months Ended

12 Months Ended

Sep. 30, 2011

Jun. 30, 2011

Mar. 31, 2011

Dec. 31, 2010

Sep. 30, 2010

Jun. 30, 2010

Mar. 31, 2010

Dec. 31, 2009

Sep. 30, 2011

Sep. 30, 2010

Sep. 30, 2009

Interest expense

$ (39)

$ (40)

$ (30)

$ (2)

$ (1)

$ (3)

$ (2)

$ (1)

$ (3)

(8)

^[1]

(7)

^[1]

(5)

^[1]

Benefit from a legal judgment

^[2]

203

166

(99)

$ 3

Colombia [Member]

Unallocated And Other [Member]

Interest expense

(39)

(40)

(30)

Certain items

^[3]

(19)

(53)

(92)

Unallocated corporate costs

^[2],[4]

^[5]

(53)

(48)

(36)

General unallocated expense income

^[6]

(32)

Executive transition cost

^[2],[4]

$ (151)

(148)

(160)

Certain Items [Member]

Restructuring charges

Write-down of impaired investments

$ 1

Impairment of long-lived assets to be disposed of

Reserve for respirator claims

$ 2

Certain Items [Member] | 2009 Global Restructuring [Member]

Restructuring charges

Environmental reserves and legal settlements

$ 3

[1]	Equity in net income of affiliated companies is included in segment EBIT and is removed from Unallocated and other to reconcile to income (loss) from operations before taxes.
[2]	Income (loss) from continuing operations before taxes for Unallocated and Other includes:
[3]	Certain items are items that management does not consider to be representative of segment results and they are, therefore, excluded from segment EBIT. Certain items for fiscal 2011 primarily include charges for global restructuring activities discussed in Note P. Certain items for fiscal 2010 include $46 million related to global restructuring activities, $3 million for environmental reserves and legal settlements, $2 million long-lived asset impairment of land related to a former carbon black site, and a $2 million addition in the reserve for respirator claims. For fiscal 2009, certain items include charges of $87 million for the Company's global restructuring activities, $4 million for executive transition costs, and $1 million for the write-down of impaired investments.
[4]	Unallocated and other includes certain items and eliminations that are not allocated to the operating segments. Management does not consider these items necessary for an understanding of the operating results of these segments and such amounts are excluded in the segment reporting to the Chief Operating Decision Maker.
[5]	Unallocated corporate costs are not controlled by the segments and primarily benefit corporate interests.
[6]	General unallocated (expense) income consists of gains (losses) arising from foreign currency transactions, net of other foreign currency risk management activities, the impact of accounting for certain inventory on a LIFO basis, and the profit or loss related to the corporate adjustment for unearned revenue. Additionally, for fiscal 2011, this amount included a $3 million charge related to a change in the net worth tax regulations in Colombia, and $3 million related to a portion of the benefit from a legal judgment.

Financial Information By Segment & Geographic Area (Revenues From External Customers And Long-Lived Asset Information By Geographic Area) (Details) - USD ($)
$ in Millions

12 Months Ended

Sep. 30, 2011

Sep. 30, 2010

Sep. 30, 2009

$ 3,102

$ 2,716

$ 2,108

^[1]

1,170

1,083

1,114

US [Member]

589

546

332

^[1]

240

233

320

China [Member]

554

458

281

Other Foreign Countries [Member]

^[1]

280

210

201

1,959

1,712

1,495

Unaudited Quarterly Financial Information

^[1]

$ 650

$ 640

$ 593

[1]	Long-lived assets include total equity and other investments, net property, plant and equipment, net intangible assets and assets held for rent.

Unaudited Quarterly Financial Information (Schedule Of Quarterly Financial Information) (Details) - USD ($)
$ / shares in Units, $ in Millions

3 Months Ended

12 Months Ended

Sep. 30, 2011

Jun. 30, 2011

Mar. 31, 2011

Dec. 31, 2010

Sep. 30, 2010

Jun. 30, 2010

Mar. 31, 2010

Dec. 31, 2009

Sep. 30, 2011

Sep. 30, 2010

Sep. 30, 2009

Net sales and other operating revenues

$ 833

$ 836

$ 739

$ 694

$ 700

$ 706

$ 676

$ 634

$ 3,102

$ 2,716

$ 2,108

Gross profit

141

152

134

131

117

136

131

126

558

510

217

Selling and administrative expenses

249

241

205

Research and technical expenses

Income from operations

243

204

(54)

Net interest expense and other charges

(14)

(13)

(6)

(7)

(8)

(6)

(15)

(9)

(40)

(38)

Income from continuing operations before taxes

203

166

(99)

(Provision) benefit for income taxes

(2)

(10)

(9)

(11)

(14)

(8)

(6)

(30)