0001564590-22-003902 | 10-Q | XBRL Viewer

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Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Dec. 31, 2021	Feb. 02, 2022
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Trading Symbol	CBT
Entity Registrant Name	Cabot Corporation
Entity Central Index Key	0000016040
Entity Current Reporting Status	Yes
Current Fiscal Year End Date	--09-30
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		56,586,811
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity File Number	1-5667
Entity Tax Identification Number	04-2271897
Entity Address, Address Line One	Two Seaport Lane
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02210-2019
City Area Code	617
Local Phone Number	345-0100
Security Exchange Name	NYSE
Title of 12(b) Security	Common Stock, $1 par value per share
Entity Incorporation, State or Country Code	DE
Document Quarterly Report	true
Document Transition Report	false
Entity Interactive Data Current	Yes

Consolidated Statements of Operations (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Statement [Abstract]
Net sales and other operating revenues	$ 968	$ 746
Cost of sales	770	553
Gross profit	198	193
Selling and administrative expenses	71	61
Research and technical expenses	13	14
Purification Solutions assets held for sale impairment charge (Note D)	197
Income (loss) from operations	(83)	118
Interest and dividend income	3	2
Interest expense	(12)	(12)
Other income (expense)	(1)	(9)
Income (loss) before income taxes and equity in earnings of affiliated companies	(93)	99
(Provision) benefit for income taxes	12	(29)
Equity in earnings of affiliated companies, net of tax	1	0
Net income (loss)	(80)	70
Net income (loss) attributable to noncontrolling interests, net of tax	9	10
Net income (loss) attributable to Cabot Corporation	$ (89)	$ 60
Weighted-average common shares outstanding:
Basic	56.8	56.5
Diluted	56.8	56.6
Earnings (loss) per common share:
Basic	$ (1.57)	$ 1.06
Diluted	$ (1.57)	$ 1.06

Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ (80)	$ 70
Other comprehensive income (loss), net of tax
Foreign currency translation adjustment, net of tax	(28)	94
Derivatives: net investment hedges
(Gains) losses reclassified to interest expense, net of tax	(1)	(1)
Pension and other postretirement benefit liability adjustments, net of tax	1	3
Other comprehensive income (loss), net of tax of $— and $(3)	(28)	96
Comprehensive income (loss)	(108)	166
Net income (loss) attributable to noncontrolling interests, net of tax	9	10
Foreign currency translation adjustment attributable to noncontrolling interests, net of tax	2	7
Comprehensive income (loss) attributable to noncontrolling interests	11	17
Comprehensive income (loss) attributable to Cabot Corporation	$ (119)	$ 149

Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (Parenthetical) $ in Millions	3 Months Ended
	Dec. 31, 2020 USD ($)
Statement Of Income And Comprehensive Income [Abstract]
Net of tax	$ (3)

- Definition

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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+ Details

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Dec. 31, 2021	Sep. 30, 2021
Current assets:
Cash and cash equivalents	$ 179	$ 168
Accounts and notes receivable, net of reserve for doubtful accounts of $4 and $4	660	645
Inventories:
Raw materials	154	168
Finished goods	341	300
Other	51	55
Total inventories	546	523
Prepaid expenses and other current assets	113	89
Assets held for sale	111
Total current assets	1,609	1,425
Property, plant and equipment, net	1,267	1,376
Goodwill	140	140
Equity affiliates	14	40
Intangible assets, net	70	100
Deferred income taxes	57	53
Other assets	158	172
Total assets	3,315	3,306
Current liabilities:
Short-term borrowings	226	72
Accounts payable and accrued liabilities	620	667
Income taxes payable	37	35
Current portion of long-term debt	373	373
Liabilities held for sale	71
Total current liabilities	1,327	1,147
Long-term debt	714	717
Deferred income taxes	73	73
Other liabilities	253	279
Contingencies (Note H)
Preferred stock:
Authorized: 2,000,000 shares of $1 par value, Issued and Outstanding: None and none
Common stock:
Authorized: 200,000,000 shares of $1 par value, Issued: 56,723,411 and 56,870,237 shares, Outstanding: 56,579,992 and 56,726,818 shares	57	57
Less cost of 143,419 and 143,419 shares of common treasury stock	(4)	(4)
Additional paid-in capital	11	24
Retained earnings	1,049	1,159
Accumulated other comprehensive income (loss)	(319)	(289)
Total Cabot Corporation stockholders' equity	794	947
Noncontrolling interests	154	143
Total stockholders' equity	948	1,090
Total liabilities and stockholders' equity	$ 3,315	$ 3,306

Consolidated Balance Sheets (Parenthetical) (Unaudited) - USD ($) $ in Millions	Dec. 31, 2021	Sep. 30, 2021
Statement Of Financial Position [Abstract]
Accounts and notes receivable, reserve for doubtful accounts	$ 4	$ 4
Preferred stock, authorized shares	2,000,000	2,000,000
Preferred stock, par value	$ 1	$ 1
Preferred stock, Issued shares	0	0
Preferred stock, Outstanding shares	0	0
Common stock, authorized shares	200,000,000	200,000,000
Common stock, par value	$ 1	$ 1
Common stock, issued shares	56,723,411	56,870,237
Common stock, outstanding shares	56,579,992	56,726,818
Common treasury stock, shares	143,419	143,419

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Cash Flows from Operating Activities:
Net income (loss)	$ (80)	$ 70
Adjustments to reconcile net income (loss) to cash provided by operating activities:
Depreciation and amortization	39	39
Purification Solutions assets held for sale impairment charge	197
Deferred tax provision (benefit)	(36)	(2)
Employee benefit plan settlement		6
Equity in earnings of affiliated companies	(1)	0
Non-cash compensation	6	4
Other non-cash (income) expense	5	5
Changes in assets and liabilities:
Accounts and notes receivable	(57)	(76)
Inventories	(95)	(37)
Prepaid expenses and other assets	(27)	(10)
Accounts payable and accrued liabilities	9	14
Income taxes payable	3	7
Other liabilities	(12)	1
Cash provided (used) by operating activities	(49)	21
Cash Flows from Investing Activities:
Additions to property, plant and equipment	(30)	(29)
Other	1
Cash provided (used) by investing activities	(29)	(29)
Cash Flows from Financing Activities:
Proceeds from issuance (repayments) of commercial paper, net	156
Proceeds from long-term debt		50
Repayments of long-term debt	(5)	(66)
Purchases of common stock	(19)	(2)
Proceeds from sales of common stock		1
Cash dividends paid to noncontrolling interests	(8)	(1)
Cash dividends paid to common stockholders	(21)	(20)
Cash provided (used) by financing activities	103	(38)
Effects of exchange rate changes on cash	(15)	42
Increase (decrease) in cash, cash equivalents and restricted cash	10	(4)
Cash, cash equivalents and restricted cash at beginning of period	170	151
Cash, cash equivalents and restricted cash at end of period	$ 180	$ 147

Consolidated Statements of Cash Flows (Parenthetical) (Unaudited) $ in Millions	Dec. 31, 2021 USD ($)
Cash and cash equivalents	$ 179
Cash, cash equivalents and restricted cash	180
Prepaid Expenses and Other Current Assets
Restricted cash classified within Prepaid expenses and other current assets	$ 1

Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Millions	Total	Common Stock, Net of Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total Cabot Corporation Stockholders' Equity [Member]	Noncontrolling Interests [Member]
Beginning Balance at Sep. 30, 2020	$ 814	$ 53		$ 989	$ (351)	$ 691	$ 123
Beginning Balance, Shares at Sep. 30, 2020		56,467
Net income (loss)	70			60		60	10
Total other comprehensive income (loss)	96				89	89	7
Cash dividends paid, Common stock, per share	(20)			(20)		(20)
Cash dividends declared to noncontrolling interests	(1)						(1)
Issuance of stock under equity compensation plans	1		$ 1			1
Issuance of stock under equity compensation plans, Shares		192
Amortization of share-based compensation	4		4			4
Purchase and retirement of common stock	(2)		(2)			(2)
Purchase and retirement of common stock, Shares		(53)
Amount reclassified to retained earnings in excess of additional paid in capital			(3)	3
Ending Balance at Dec. 31, 2020	962	$ 53		1,032	(262)	823	139
Ending Balance, Shares at Dec. 31, 2020		56,606
Beginning Balance at Sep. 30, 2021	1,090	$ 53	24	1,159	(289)	947	143
Beginning Balance, Shares at Sep. 30, 2021		56,727
Net income (loss)	(80)			(89)		(89)	9
Total other comprehensive income (loss)	(28)				(30)	(30)	2
Cash dividends paid, Common stock, per share	(21)			(21)		(21)
Issuance of stock under equity compensation plans, Shares		202
Amortization of share-based compensation	6		6			6
Purchase and retirement of common stock	(19)		(19)			(19)
Purchase and retirement of common stock, Shares		(349)
Ending Balance at Dec. 31, 2021	$ 948	$ 53	$ 11	$ 1,049	$ (319)	$ 794	$ 154
Ending Balance, Shares at Dec. 31, 2021		56,580

Consolidated Statements of Changes in Stockholders' Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Statement Of Stockholders Equity [Abstract]
Common stock, cash dividends paid, per share	$ 0.37	$ 0.35

Basis of Presentation

3 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Basis of Presentation

A. Basis of Presentation

The consolidated financial statements have been prepared in conformity with accounting policies generally accepted in the United States (“U.S.”) and include the accounts of Cabot Corporation (“Cabot” or the “Company”) 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. Intercompany transactions have been eliminated in consolidation.

The unaudited consolidated financial statements have been prepared in accordance with the requirements of Form 10-Q and consequently do not include all disclosures required by Form 10-K. Additional information may be obtained by referring to Cabot’s Annual Report on Form 10-K for its fiscal year ended September 30, 2021 (“2021 10-K”).

The financial information submitted herewith is unaudited and reflects all adjustments which are, in the opinion of management, necessary to provide a fair statement of the results for the interim periods ended December 31, 2021 and 2020. All such adjustments are of a normal recurring nature. The results for interim periods are not necessarily indicative of the results to be expected for the fiscal year.

Significant Accounting Policies

3 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Significant Accounting Policies

B. Significant Accounting Policies

Recently Adopted Accounting Standards

In December 2019, the FASB issued a new standard Simplifying the Accounting for Income Taxes. The new guidance simplifies the accounting for income taxes by removing several exceptions in the current standard and adding guidance that reduces complexity in certain areas. The new standard is effective for fiscal years beginning after December 15, 2020. The Company adopted this standard on October 1, 2021. The adoption of this standard did not materially impact the Company’s consolidated financial statements.

Recent Accounting Pronouncements

In March 2020, the FASB issued a new standard on Reference Rate Reform, which provides temporary optional expedients and exceptions to the existing guidance on contract modifications and hedge accounting to ease the financial reporting burdens related to the expected market transition from the London Interbank Offered Rate ("LIBOR") and other interbank offered rates to alternative reference rates. The standard was effective upon issuance and may generally be applied through December 31, 2022 to any new or amended contracts, hedging relationships, and other transactions that reference LIBOR. The Company is currently evaluating the timing of adoption and the impact of the adoption of this standard on its consolidated financial statements.

Acquisitions

3 Months Ended

Dec. 31, 2021

Business Combinations [Abstract]

Acquisitions

C. Acquisitions

Tokai Carbon (Tianjin) Co.

In November 2021, Cabot entered into an agreement with Tokai Carbon Group to purchase its carbon black manufacturing facility in Tianjin, China, Tokai Carbon (Tianjin) Co., for approximately $9 million, which is subject to the satisfaction or waiver of customary closing adjustments. The purchase is expected to close in the second quarter of fiscal 2022.

Divestiture

3 Months Ended

Dec. 31, 2021

Discontinued Operations And Disposal Groups [Abstract]

Divestiture

D. Divestiture

Pending Sale of Purification Solutions Business

In November 2021, the Company and an affiliate of funds advised by One Equity Partners (“OEP”) entered into a Share Purchase Agreement (the “Agreement”) for the sale of Cabot’s Purification Solutions business (the “Business”), a reporting segment of the Company, subject to the satisfaction or waiver of the conditions set forth in the Agreement.

Under the terms of the Agreement, OEP will acquire the Business on a cash-free and debt-free basis in a transaction valued at approximately $111 million, subject to certain debt-like and other closing adjustments, including a customary working capital adjustment. The net cash proceeds from the transaction are expected to be approximately $80 million, to be paid at the closing. The transaction is expected to close in the second quarter of fiscal 2022.

During the first quarter of fiscal 2022, the assets and liabilities of the Business met the criteria for assets held for sale. The sale of the Business does not meet the criteria to be reported as a discontinued operation as it does not constitute a significant strategic business shift that will have a major effect on the Company’s operations and financial results.

In addition, based on the carrying value of the Business as of December 31, 2021 and an estimate of its fair value less costs to sell, Cabot recorded a pre-tax impairment charge of $197 million ($160 million after-tax) in the first quarter of fiscal 2022.

The following table summarizes the carrying amounts of the major classes of assets and liabilities of the Business classified as held for sale as of December 31, 2021, and the associated impairment charge:

	(In millions)
Assets
Accounts and notes receivable, net of reserve for doubtful accounts	$	37
Inventories		67
Prepaid expenses and other current assets		2
Property, plant and equipment, net		106
Equity affiliates		28
Intangible assets, net		27
Deferred income taxes		31
Other assets		10
Total assets held for sale		308
Impairment of assets held for sale		(197	)
Adjusted assets held for sale	$	111

Liabilities
Short-term borrowings	$	(2	)
Accounts payable and accrued liabilities		(51	)
Income taxes payable		(1	)
Long-term debt		(17	)
Total liabilities assumed		(71	)
Total net assets held for sale	$	40

Sale of Marshall Mine

In September 2020, the Company entered into an agreement to sell its lignite mine located in Marshall, Texas to ADA Carbon Solutions, LLC (“ADACS”) for a nominal amount. As part of the transaction, the Company agreed to fund a portion of the costs ADACS expects to incur to close the mine. Additionally, in conjunction with the sale, the Business entered into a long-term supply agreement with ADACS, a producer of lignite-based activated carbon, which included an agreement for the Company to fund certain capital expenditures. As of December 31, 2021, $11 million was included in Accounts payable and accrued liabilities on the Consolidated Balance Sheets for these mine closure costs and capital expenditures. In connection with the sale of the Business, the Company plans to settle this liability in full with ADACS in the second quarter of fiscal 2022.

Employee Benefit Plans

3 Months Ended

Dec. 31, 2021

Compensation And Retirement Disclosure [Abstract]

Employee Benefit Plans

E. Employee Benefit Plans

Net periodic defined benefit pension costs include the following:

	Three Months Ended December 31
	2021			2020
	Pension Benefits
	(In millions)
Service cost	$	1		$	1
Interest cost		1			1
Expected return on plan assets		(2	)		(2	)
Amortization of actuarial loss		—			1
Settlement charge⁽¹⁾		—			6
Net periodic benefit (credit) cost	$	—		$	7

⁽¹⁾In the first quarter of fiscal 2021, the Company recognized a $6 million settlement charge in Other income (expense) in the Consolidated Statements of Operations related to the final asset transfers associated with the termination of the Company’s U.S. qualified pension plan.

Other postretirement benefit costs were less than $1 million for each of the three months ended December 31, 2021 and 2020.

- Definition

The entire disclosure for retirement benefits.

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+ Details

Goodwill and Intangible Assets

3 Months Ended

Dec. 31, 2021

Goodwill And Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets

F. Goodwill and Intangible Assets

The carrying amount of goodwill attributable to each reportable segment with goodwill balances and the changes in those balances during the three months ended December 31, 2021 are as follows:

	Reinforcement Materials		Performance Chemicals		Total
	(In millions)
Balance at September 30, 2021	$	48	$	92	$	140
Foreign currency impact		—		—		—
Balance at December 31, 2021	$	48	$	92	$	140

The following table provides information regarding the Company’s intangible assets:

	December 31, 2021							September 30, 2021
	Gross Carrying Value		Accumulated Amortization			Net Intangible Assets		Gross Carrying Value		Accumulated Amortization			Net Intangible Assets
	(In millions)
Intangible assets with finite lives
Developed technologies⁽¹⁾	$	36	$	(7	)	$	29	$	62	$	(12	)	$	50
Trademarks⁽¹⁾		2		—			2		11		(1	)		10
Customer relationships		60		(21	)		39		60		(20	)		40
Total intangible assets	$	98	$	(28	)	$	70	$	133	$	(33	)	$	100

⁽¹⁾

Developed technologies intangible assets with a carrying value of $25 million and accumulated amortization of $5 million and trademark intangible assets with a carrying value of $8 million and accumulated amortization of $1 million related to the Purification Solutions business were classified as assets held for sale as of December 31, 2021.

Intangible assets are amortized over their estimated useful lives, which range between ten and twenty-five years, with a weighted average amortization period of approximately seventeen years. Amortization expense was $2 million for each of the three months ended December 31, 2021 and 2020 and is included in Cost of sales, Selling and administrative expenses and Research and technical expenses in the Consolidated Statements of Operations. Total amortization expense is estimated to be approximately $6 million each year for the next five fiscal years.

Accumulated Other Comprehensive Income (Loss) (“AOCI”)

3 Months Ended

Dec. 31, 2021

Stockholders Equity Note [Abstract]

Accumulated Other Comprehensive Income (Loss) (“AOCI”)

G. Accumulated Other Comprehensive Income (Loss) (“AOCI”)

Comprehensive income combines net income (loss) and other comprehensive income items, which are reported as components of stockholders’ equity in the accompanying Consolidated Balance Sheets.

Changes in each component of AOCI, net of tax, were as follows:

	Currency Translation Adjustment			Pension and Other Postretirement Benefit Liability Adjustments			Total
	(In millions)
Balance at September 30, 2021, attributable to Cabot Corporation	$	(265	)	$	(24	)	$	(289	)
Other comprehensive income (loss) before reclassifications		(28	)		1			(27	)
Amounts reclassified from AOCI		(1	)		—			(1	)
Less: Other comprehensive income (loss) attributable to noncontrolling interests		2			—			2
Balance at December 31, 2021, attributable to Cabot Corporation	$	(296	)	$	(23	)	$	(319	)

The amounts reclassified out of AOCI and into the Consolidated Statements of Operations in each of the three months ended December 31, 2021 and 2020 were as follows:

	Affected Line Item in the Consolidated	Three Months Ended December 31
	Statements of Operations	2021			2020
		(In millions)
Derivatives: net investment hedges
(Gains) losses reclassified to interest expense	Interest expense	$	(1	)	$	(1	)
Pension and other postretirement
Amortization of actuarial losses and prior service cost (credit)	Net Periodic Benefit Cost (Note E)		—			1
Settlement charge	Net Periodic Benefit Cost (Note E)		—			6
Total before tax		$	(1	)	$	6

Contingencies

3 Months Ended

Dec. 31, 2021

Commitments And Contingencies Disclosure [Abstract]

Contingencies

H. Contingencies

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. As more fully described in the 2021 10-K, the respirator liabilities generally involve claims for personal injury, including asbestosis, silicosis and coal worker’s pneumoconiosis, allegedly resulting from the use of respirators that are alleged to have been negligently designed and/or labeled. At no time did this respiratory product line represent a significant portion of the respirator market. In addition to Cabot’s subsidiary, other parties are responsible for significant portions of the costs of these respirator liabilities (as defined in the 2021 10-K, the “Payor Group”).

Cabot has a reserve to cover its expected share of liabilities for pending and future respirator liability claims, which is included in Other liabilities and Accounts payable and accrued liabilities on the Consolidated Balance Sheets. The Company expects these liabilities to be incurred over a number of years. The reserve was $44 million at both December 31, 2021 and September 30, 2021.

The Company’s current estimate of the cost of its share of pending and future respirator liability claims is based on facts and circumstances existing at this time, including the number and nature of the remaining claims. Developments that could affect the Company’s 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 claims, (iii) significant changes in the average cost of resolving claims, including potential settlements of groups of claims, (iv) significant changes in the legal costs of defending these claims, (v) changes in the nature of claims received or changes in our assessment of the viability of these claims, (vi) trial and appellate outcomes, (vii) changes in the law and procedure applicable to these claims, (viii) the financial viability of the parties that contribute to the payment of respirator claims, (ix) exhaustion or changes in the recoverability of the insurance coverage maintained by certain members of the Payor Group, or a change in the availability of the indemnity provided by a former owner of AO, (x) changes in the allocation of costs among the various parties paying legal and settlement costs, and (xi) a determination that the assumptions that were used to estimate Cabot’s share of liability are no longer reasonable. The Company cannot determine the impact of these potential developments on its current estimate of its share of liability for existing and future claims. Because reserves are limited to amounts that are probable and estimable as of a relevant measurement date, and there is inherent difficulty in projecting the impact of potential developments on Cabot’s share of liability for these existing and future claims, it is reasonably possible that the liabilities for existing and future claims could change in the near term and that change could be material.

Insurance Recoveries - Pepinster, Belgium

In July 2021, the Company’s Specialty Compounds manufacturing and research and development facility in Pepinster, Belgium experienced significant flooding. Full production is temporarily halted and is not expected to resume until the second quarter of fiscal 2022. During fiscal 2021, the Company recorded expenses of $17 million for clean-up costs, inventory, and fixed asset impairments and simultaneously recognized a fully offsetting loss recovery from expected insurance proceeds.

During the first quarter of fiscal 2022 the Company recorded additional expenses of $5 million for clean-up costs, inventory, and fixed asset impairments and simultaneously recognized a fully offsetting loss recovery from expected insurance proceeds as the Company expects insurance proceeds in excess of the total incurred costs and policy deductibles. The flood-related expenses and loss recovery are both included within Cost of sales in the Consolidated Statements of Operations for the first quarter of fiscal 2022.

During fiscal 2021, the Company received insurance proceeds of $8 million. During the first quarter of fiscal 2022, the Company received additional insurance proceeds of $5 million which is included in Cash provided by operating activities in the Consolidated Statements of Cash Flows for the first quarter of fiscal 2022. At both December 31, 2021 and September 30, 2021 the receivable for insurance recoveries was $9 million and is included in Accounts and notes receivable on the Consolidated Balance Sheet.

Other Matters

The Company has various other lawsuits, claims and contingent liabilities arising in the ordinary course of its business and with respect to its divested businesses. The Company does not believe that any of these matters will have a material adverse effect on its financial position; however, litigation is inherently unpredictable. Cabot could incur judgments, enter into settlements or revise its expectations regarding the outcome of certain matters, and such developments could have a material impact on its results of operations in the period in which the amounts are accrued or its cash flows in the period in which the amounts are paid.

Income Tax

3 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Income Tax

I. Income Tax

Effective Tax Rate

	Three Months Ended December 31
	2021			2020
	(Dollars in millions)
(Provision) benefit for income taxes	$	12		$	(29	)
Effective tax rate		13	%		29	%

For the three months ended December 31, 2021, the (Provision) benefit for income taxes included a net discrete tax benefit of $37 million after valuation allowance which was recorded as part of the pending Purification Solutions business divestiture and assets held for sale impairment. For the three months ended December 31, 2020, the (Provision) benefit for income taxes included a net discrete tax expense of $2 million.

Income tax in Interim Periods

The Company records its tax provision or benefit on an interim basis using an estimated annual effective tax rate. This rate is applied to the current period ordinary income or loss to determine the income tax provision or benefit allocated to the interim period. The income tax effects of unusual or infrequent items are excluded from the estimated annual effective tax rate and are recognized in the impacted interim period. Losses from jurisdictions for which no benefit can be recognized are excluded from the overall computations of the estimated annual effective tax rate and a separate estimated annual effective tax rate is computed and applied to ordinary income or loss in the loss jurisdiction.

Valuation allowances are provided against the future tax benefits that arise from the deferred tax assets in jurisdictions for which no benefit can be recognized. The estimated annual effective tax rate may be significantly impacted by nondeductible expenses and the Company’s projected earnings mix by tax jurisdiction. Adjustments to the estimated annual effective income tax rate are recognized in the period when such estimates are revised.

Uncertainties

Cabot and certain subsidiaries are under audit in a number of jurisdictions. In addition, certain statutes of limitations are scheduled to expire in the near future. It is reasonably possible that a change in the unrecognized tax benefits may also 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 2018 through 2020 tax years generally remain subject to examination by the IRS and various tax years from 2005 through 2020 remain subject to examination by the respective state tax authorities. In significant non-U.S. jurisdictions, various tax years from 2005 through 2020 remain subject to examination by their respective tax authorities.

During each of the three months ended December 31, 2021 and 2020, Cabot released uncertain tax positions of $1 million, due to the expiration of statutes of limitations in various jurisdictions.

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 270
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6424409&loc=d3e44925-109338

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI http://asc.fasb.org/topic&trid=2144680

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Earnings Per Share

3 Months Ended

Dec. 31, 2021

Earnings Per Share [Abstract]

Earnings Per Share

J. Earnings Per Share

The following tables summarize the components of the basic and diluted earnings (loss) per common share (“EPS”) computations:

	Three Months Ended December 31
	2021			2020
	(In millions, except per share amounts)
Basic EPS:
Net income (loss) attributable to Cabot Corporation	$	(89	)	$	60
Less: Dividends and dividend equivalents to participating securities		—			—
Less: Undistributed earnings allocated to participating securities⁽¹⁾		—			—
Earnings (loss) allocated to common shareholders (numerator)	$	(89	)	$	60

Weighted average common shares and participating securities outstanding		57.7			57.2
Less: Participating securities⁽¹⁾		0.9			0.7
Adjusted weighted average common shares (denominator)		56.8			56.5

Earnings (loss) per common share - basic:	$	(1.57	)	$	1.06

Diluted EPS:
Earnings (loss) allocated to common shareholders	$	(89	)	$	60
Plus: Earnings allocated to participating securities		—			—
Less: Adjusted earnings allocated to participating securities⁽²⁾		—			—
Earnings (loss) allocated to common shareholders (numerator)	$	(89	)	$	60

Adjusted weighted average common shares outstanding		56.8			56.5
Effect of dilutive securities:
Common shares issuable⁽³⁾		—			0.1
Adjusted weighted average common shares (denominator)		56.8			56.6

Earnings (loss) per common share - diluted:	$	(1.57	)	$	1.06

⁽¹⁾

Participating securities consist of shares underlying all outstanding and achieved performance-based restricted stock units and all unvested time-based restricted stock units. The holders of these units are entitled to receive dividend equivalents payable in cash to the extent dividends are paid on the Company’s outstanding common stock and equal in value to the dividends that would have been paid in respect of the shares underlying such 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:

	Three Months Ended December 31
	2021			2020
	(In millions)
Calculation of undistributed earnings (loss):
Net income (loss) attributable to Cabot Corporation	$	(89	)	$	60
Less: Dividends declared on common stock		21			20
Less: Dividends declared on participating securities		—			—
Undistributed earnings (loss)	$	(110	)	$	40

Allocation of undistributed earnings (loss):
Undistributed earnings (loss) allocated to common shareholders	$	(110	)	$	40
Undistributed earnings allocated to participating shareholders		—			—
Undistributed earnings (loss)	$	(110	)	$	40

⁽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; and (ii) assumed issuance of shares to employees pursuant to the Company’s Deferred Compensation and Supplemental Retirement Plan. For the three months ended December 31, 2021, 2,356,941 incremental shares of common stock, which includes shares of participating securities as described in (1) above, were excluded from the calculation of diluted earnings per share because the inclusion of these shares would have been antidilutive due to the Company’s net loss position. For the three months ended December 31, 2020, 1,305,993 incremental shares of common stock were excluded from the calculation of diluted earnings per share because the inclusion of these shares would have been antidilutive.

Restructuring

3 Months Ended

Dec. 31, 2021

Restructuring And Related Activities [Abstract]

Restructuring

K. Restructuring

Cabot’s restructuring activities were recorded in the Consolidated Statements of Operations in the three months ended December 31, 2021 and 2020 as follows:

	Three Months Ended December 31
	2021		2020
	(In millions)
Cost of sales	$	1	$	3
Selling and administrative expenses		1		—
Total	$	2	$	3

Details of all restructuring activities and the related reserves during the three months ended December 31, 2021 were as follows:

	Severance and Employee Benefits			Environmental Remediation		Total
	(In millions)
Reserve at September 30, 2021	$	5		$	4	$	9
Charges (gain)		2			—		2
Cash paid		(2	)		—		(2	)
Reserve at December 31, 2021	$	5		$	4	$	9

Cabot’s severance and employee benefit reserves and other closure related reserves are reflected in Accounts payable and accrued liabilities on the Company’s Consolidated Balance Sheets. Cabot’s environmental remediation reserves related to restructuring activities are reflected in Other liabilities on the Company’s Consolidated Balance Sheets.

Reorganization Actions

Beginning in fiscal 2020, the Company has been undertaking various actions that it believes will enable it to perform certain activities more effectively. These actions have primarily consisted of the reorganization of Cabot’s leadership structure, the creation of a Global Business Services function and other operational efficiency initiatives. As of December 31, 2021, the Company had recorded total charges of $24 million, of which $22 million was recorded in prior fiscal years, primarily related to severance costs, and also had $4 million of accrued severance charges in the Consolidated Balance Sheets related to these actions. The Company expects to record additional restructuring charges of approximately $1 million throughout the rest of fiscal 2022 and $2 million thereafter, primarily related to severance and site demolition costs associated with these reorganization activities. As of December 31, 2021, the Company had paid a total of $19 million in cash, of which $18 million was paid in prior fiscal years, and expects to have future cash outlays of approximately $4 million in the remainder of fiscal 2022 and $3 million thereafter related to these reorganization activities.

Financial Instruments and Fair Value Measurements

3 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

Financial Instruments and Fair Value Measurements

L. Financial Instruments and Fair Value Measurements

The FASB authoritative guidance on fair value measurements defines fair value, provides a framework for measuring fair value, and requires certain disclosures about fair value measurements. The required disclosures focus on the inputs used to measure fair value. The guidance establishes the following hierarchy for categorizing these inputs:

Level 1	—	Quoted market prices in active markets for identical assets or liabilities

Level 2	—	Significant other observable inputs (e.g., quoted prices for similar items in active markets, quoted prices for identical or similar items in markets that are not active, inputs other than quoted prices that are observable such as interest rate and yield curves, and market-corroborated inputs)

Level 3	—	Significant unobservable inputs

There were no transfers of financial assets or liabilities measured at fair value between Level 1 and Level 2 and there were no Level 3 investments during the first three months of either fiscal 2022 or 2021.

At December 31, 2021 and September 30, 2021, Cabot had derivatives relating to foreign currency risks, including a net investment hedge and forward foreign currency contracts, carried at fair value. At December 31, 2021, the fair value of these derivatives was a net asset of $3 million and was included in Prepaid expenses and other current assets, and Other assets on the Consolidated Balance Sheets. At September 30, 2021, the fair value of these derivatives was a net asset of $3 million and was included in Prepaid expenses and other current assets, Accounts payable and accrued liabilities, and Other assets on the Consolidated Balance Sheets. These derivatives are classified as Level 2 instruments within the fair value hierarchy as the fair value determination was based on observable inputs.

At each of December 31, 2021 and September 31, 2021, the fair value of guaranteed investment contracts included in Other assets on the Consolidated Balance Sheets was $10 million. Guaranteed investment contracts were classified as Level 2 instruments within the fair value hierarchy as the fair value determination was based on other observable inputs.

At December 31, 2021 and September 30, 2021, the fair values of cash and cash equivalents, accounts and notes receivable, accounts payable and accrued liabilities, and short-term borrowings and variable rate debt approximated their carrying values due to the short-term nature of these instruments. The carrying value and fair value of the long-term fixed rate debt were $1.06 billion and $1.12 billion, respectively, as of December 31, 2021, and $1.06 billion and $1.13 billion, respectively, as of September 30, 2021. The fair values of Cabot’s fixed rate long-term debt are estimated based on comparable quoted market prices at the respective period ends. The carrying amounts of Cabot’s floating rate long-term debt and finance and operating lease obligations approximate their fair values. All such measurements are based on observable inputs and are classified as Level 2 within the fair value hierarchy. The valuation technique used is the discounted cash flow model.

Derivatives

3 Months Ended

Dec. 31, 2021

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Derivatives

M. Derivatives

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 Euro-denominated principal and interest payments.

Additionally, the Company has foreign currency exposure arising from its net investments in foreign operations. Cabot may enter 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 monetary 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. 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 December 31, 2021 and September 30, 2021 to manage foreign currency risk.

		Notional Amount
Description	Borrowing	December 31, 2021	September 30, 2021	Hedge Designation
Cross-Currency Swaps	3.4% Notes	USD 250 million swapped to EUR 223 million	USD 250 million swapped to EUR 223 million	Net investment
Forward Foreign Currency Contracts ⁽¹⁾	N/A	USD 36 million	USD 48 million	No designation

⁽¹⁾	^{As of both December 31, 2021 and September 30, 2021, Cabot’s forward foreign exchange contracts were denominated in Indonesian rupiah and Czech koruna and the fair value of these derivative instruments were a nominal amount.}

Accounting for Derivative Instruments and Hedging Activities

The Company has cross-currency swaps with a notional amount of $250 million, which are designated as hedges of its net investments in certain Euro-denominated subsidiaries. Cash settlements occur semi-annually on March 15^th and September 15^th for fixed rate interest payments and a cash exchange of the notional currency amount will occur at the end of the term in 2026. As of December 31, 2021, the fair value of these swaps was an asset of $3 million and was included in Prepaid expenses and other current assets and Other assets and the cumulative gain of $5 million was included in AOCI on the Consolidated Balance Sheets. As of September 30, 2021, the fair value of these swaps was an asset of $3 million and was included in Prepaid expenses and other current assets and Other assets, and the cumulative gain of $6 million was included in AOCI on the Consolidated Balance Sheets.

The following table summarizes the impact of the cross-currency swaps to AOCI and the Consolidated Statements of Operations:

	Three Months Ended December 31
	2021		2020			2021			2020			2021		2020
Description	Gain/(Loss) Recognized in AOCI					(Gain)/Loss Reclassified from AOCI into Interest Expense in the Consolidated Statements of Operations						(Gain)/Loss Recognized in Interest Expense in the Consolidated Statements of Operations (Amount Excluded from Effectiveness Testing)
	(In millions)
Cross-currency swaps	$	—	$	(13	)	$	(1	)	$	(1	)	$	—	$	—

Financial Information by Segment

3 Months Ended

Dec. 31, 2021

Segment Reporting [Abstract]

Financial Information by Segment

N. Financial Information by Segment

The Company identifies a product line as an operating segment if: i) it engages in business activities from which it may earn revenues and incur expenses; ii) its operating results are regularly reviewed by the Chief Operating Decision Maker (“CODM”), who is Cabot’s President and Chief Executive Officer, to make decisions about resources to be allocated to the segment and assess its performance; and iii) it has available discrete financial information. The CODM reviews financial information at the operating segment level to allocate resources and to assess the operating results and financial performance for each operating segment. Operating segments are aggregated into a reportable segment if the operating segments are determined to have similar economic characteristics and if the operating segments are similar in the following areas: i) nature of products and services; ii) nature of production processes; iii) type or class of customer for their products and services; iv) methods used to distribute the products or provide services; and v) if applicable, the nature of the regulatory environment.

The Company has three reportable segments: Reinforcement Materials, Performance Chemicals and Purification Solutions. In November 2021, the Company entered into an agreement to sell the Purification Solutions business as discussed in Note D. Upon consummation of the transaction, the Company will be organized into two reportable segments.

The Reinforcement Materials segment combines the reinforcing carbons and engineered elastomer composites product lines.

The Performance Chemicals segment combines the specialty carbons, fumed metal oxides, battery materials and aerogel product lines into the Performance Additives business, and combines the specialty compounds and inkjet colorants product lines into the Formulated Solutions business. These businesses are similar in terms of economic characteristics, nature of products, processes, customer class and product distribution methods, and therefore have been aggregated into one reportable segment. The net sales from each of these businesses for the three months ended December 31, 2021 and 2020 were as follows:

	Three Months Ended December 31
	2021		2020
	(In millions)
Performance Additives	$	227	$	184
Formulated Solutions		75		83
Total Performance Chemicals	$	302	$	267

The Purification Solutions segment consists of the Company’s activated carbon business.

Income (loss) before income taxes (“Segment EBIT”) is presented for each reportable segment in the table below. Segment EBIT excludes Interest expense, general unallocated income (expense), unallocated corporate costs, and certain items, meaning items management does not consider representative of on-going operating segment results. In addition, Segment EBIT includes Equity in earnings of affiliated companies, net of tax, the full operating results of a contractual joint venture in Purification Solutions, royalties, Net income attributable to noncontrolling interests, net of tax, and discounting charges for certain Notes receivable.

Financial information by reportable segment is as follows:

	Reinforcement Materials		Performance Chemicals		Purification Solutions			Segment Total		Unallocated and Other⁽¹⁾			Consolidated Total
	(In millions)
Three Months Ended December 31, 2021
Revenues from external customers⁽²⁾	$	541	$	302	$	61		$	904	$	64		$	968
Income (loss) before income taxes⁽³⁾	$	85	$	52	$	—		$	137	$	(230	)	$	(93	)

Three Months Ended December 31, 2020
Revenues from external customers⁽²⁾	$	375	$	267	$	59		$	701	$	45		$	746
Income (loss) before income taxes⁽³⁾	$	88	$	54	$	(2	)	$	140	$	(41	)	$	99

⁽¹⁾	^{Unallocated and Other includes certain items and eliminations necessary to reflect management’s reporting of operating segment results. These items are reflective of the segment reporting presented to the CODM.}

⁽²⁾

Consolidated Total Revenues from external customers reconciles to Net sales and other operating revenues on the Consolidated Statements of Operations. Revenues from external customers that are categorized as Unallocated and Other reflects royalties, external shipping and handling fees, the impact of unearned revenue, the removal of 100% of the sales of an equity method affiliate, discounting charges for certain Notes receivable, and by-product revenue. Details are provided in the table below:

	Three Months Ended December 31
	2021			2020
	(In millions)
Shipping and handling fees	$	39		$	33
By-product sales		28			17
Other		(3	)		(5	)
Total	$	64		$	45

⁽³⁾	Consolidated Total Income (loss) before income taxes reconciles to Income (loss) before income taxes and equity in earnings of affiliated companies on the Consolidated Statements of Operations. Income (loss) before income taxes that are categorized as Unallocated and Other includes:

	Three Months Ended December 31
	2021			2020
	(In millions)
Interest expense	$	(12	)	$	(12	)
Certain items^(a)
Purification Solutions assets held for sale impairment charge (Note D)		(197	)		—
Divestiture related charges		(4	)		—
Global restructuring activities (Note K)		(2	)		(3	)
Legal and environmental matters and reserves		(1	)		—
Acquisition and integration-related charges		(1	)		(1	)
Employee benefit plan settlement and other charges		—			(6	)
Other		1			(1	)
Total certain items, pre-tax		(204	)		(11	)
Unallocated corporate costs^(b)		(14	)		(13	)
General unallocated income (expense)^(c)		1			(5	)
Less: Equity in earnings of affiliated companies, net of tax^(d)		1			—
Total	$	(230	)	$	(41	)

^(a)

Certain items are items of expense and income that management does not consider representative of the Company’s fundamental on-going segment results and they are, therefore, excluded from Segment EBIT.

^(b)

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

^(c)

General unallocated income (expense) consists of gains (losses) arising from foreign currency transactions, net of other foreign currency risk management activities, Interest and dividend income, the profit or loss related to the corporate adjustment for unearned revenue, the impact of including the full operating results of a contractual joint venture in Purification Solutions Segment EBIT and unrealized holding gains (losses) for equity securities.

^(d)

Equity in earnings of affiliated companies, net of tax, is included in Segment EBIT and is removed in Unallocated and other to reconcile to Income (loss) from operations before income taxes and equity in earnings from affiliated companies.

The Company’s segments operate globally. In addition to presenting Revenue from external customers by reportable segment, the following tables further disaggregate Revenues from external customers by geographic region.

	Three Months Ended December 31, 2021
	Reinforcement Materials		Performance Chemicals		Purification Solutions		Consolidated Total
	(In millions)
Americas	$	206	$	90	$	27	$	323
Asia Pacific		240		136		8		384
Europe, Middle East and Africa		95		76		26		197
Segment revenues from external customers		541		302		61		904
Unallocated and other								64
Net sales and other operating revenues							$	968

	Three Months Ended December 31, 2020
	Reinforcement Materials		Performance Chemicals		Purification Solutions		Consolidated Total
	(In millions)
Americas	$	149	$	69	$	25	$	243
Asia Pacific		155		118		9		282
Europe, Middle East and Africa		71		80		25		176
Segment revenues from external customers		375		267		59		701
Unallocated and other								45
Net sales and other operating revenues							$	746

- Definition

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.

+ References

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+ Details

Significant Accounting Policies (Policies)	3 Months Ended
Significant Accounting Policies (Policies)	Dec. 31, 2021
Accounting Policies [Abstract]
Recently Adopted Accounting Standards	Recently Adopted Accounting Standards In December 2019, the FASB issued a new standard Simplifying the Accounting for Income Taxes. The new guidance simplifies the accounting for income taxes by removing several exceptions in the current standard and adding guidance that reduces complexity in certain areas. The new standard is effective for fiscal years beginning after December 15, 2020. The Company adopted this standard on October 1, 2021. The adoption of this standard did not materially impact the Company’s consolidated financial statements.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In March 2020, the FASB issued a new standard on Reference Rate Reform, which provides temporary optional expedients and exceptions to the existing guidance on contract modifications and hedge accounting to ease the financial reporting burdens related to the expected market transition from the London Interbank Offered Rate ("LIBOR") and other interbank offered rates to alternative reference rates. The standard was effective upon issuance and may generally be applied through December 31, 2022 to any new or amended contracts, hedging relationships, and other transactions that reference LIBOR. The Company is currently evaluating the timing of adoption and the impact of the adoption of this standard on its consolidated financial statements.

Divestiture (Tables)

3 Months Ended

Dec. 31, 2021

Discontinued Operations And Disposal Groups [Abstract]

Summary of Major Classes of Assets and Liabilities of the Business Classified as Held for Sale

	(In millions)
Assets
Accounts and notes receivable, net of reserve for doubtful accounts	$	37
Inventories		67
Prepaid expenses and other current assets		2
Property, plant and equipment, net		106
Equity affiliates		28
Intangible assets, net		27
Deferred income taxes		31
Other assets		10
Total assets held for sale		308
Impairment of assets held for sale		(197	)
Adjusted assets held for sale	$	111

Liabilities
Short-term borrowings	$	(2	)
Accounts payable and accrued liabilities		(51	)
Income taxes payable		(1	)
Long-term debt		(17	)
Total liabilities assumed		(71	)
Total net assets held for sale	$	40

- Definition

Tabular disclosure of information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.

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+ Details

Employee Benefit Plans (Tables)

3 Months Ended

Dec. 31, 2021

Compensation And Retirement Disclosure [Abstract]

Net Periodic Defined Benefit Pension Costs

Net periodic defined benefit pension costs include the following:

	Three Months Ended December 31
	2021			2020
	Pension Benefits
	(In millions)
Service cost	$	1		$	1
Interest cost		1			1
Expected return on plan assets		(2	)		(2	)
Amortization of actuarial loss		—			1
Settlement charge⁽¹⁾		—			6
Net periodic benefit (credit) cost	$	—		$	7

Goodwill and Intangible Assets (Tables)

3 Months Ended

Dec. 31, 2021

Goodwill And Intangible Assets Disclosure [Abstract]

Schedule of Goodwill Balances

The carrying amount of goodwill attributable to each reportable segment with goodwill balances and the changes in those balances during the three months ended December 31, 2021 are as follows:

	Reinforcement Materials		Performance Chemicals		Total
	(In millions)
Balance at September 30, 2021	$	48	$	92	$	140
Foreign currency impact		—		—		—
Balance at December 31, 2021	$	48	$	92	$	140

Schedule of Intangible Assets

The following table provides information regarding the Company’s intangible assets:

	December 31, 2021							September 30, 2021
	Gross Carrying Value		Accumulated Amortization			Net Intangible Assets		Gross Carrying Value		Accumulated Amortization			Net Intangible Assets
	(In millions)
Intangible assets with finite lives
Developed technologies⁽¹⁾	$	36	$	(7	)	$	29	$	62	$	(12	)	$	50
Trademarks⁽¹⁾		2		—			2		11		(1	)		10
Customer relationships		60		(21	)		39		60		(20	)		40
Total intangible assets	$	98	$	(28	)	$	70	$	133	$	(33	)	$	100

⁽¹⁾

Accumulated Other Comprehensive Income (Loss) (“AOCI”) (Tables)

3 Months Ended

Dec. 31, 2021

Equity [Abstract]

Changes in Each Component of AOCI, Net of Tax

Changes in each component of AOCI, net of tax, were as follows:

	Currency Translation Adjustment			Pension and Other Postretirement Benefit Liability Adjustments			Total
	(In millions)
Balance at September 30, 2021, attributable to Cabot Corporation	$	(265	)	$	(24	)	$	(289	)
Other comprehensive income (loss) before reclassifications		(28	)		1			(27	)
Amounts reclassified from AOCI		(1	)		—			(1	)
Less: Other comprehensive income (loss) attributable to noncontrolling interests		2			—			2
Balance at December 31, 2021, attributable to Cabot Corporation	$	(296	)	$	(23	)	$	(319	)

Amounts Reclassified Out of AOCI

The amounts reclassified out of AOCI and into the Consolidated Statements of Operations in each of the three months ended December 31, 2021 and 2020 were as follows:

	Affected Line Item in the Consolidated	Three Months Ended December 31
	Statements of Operations	2021			2020
		(In millions)
Derivatives: net investment hedges
(Gains) losses reclassified to interest expense	Interest expense	$	(1	)	$	(1	)
Pension and other postretirement
Amortization of actuarial losses and prior service cost (credit)	Net Periodic Benefit Cost (Note E)		—			1
Settlement charge	Net Periodic Benefit Cost (Note E)		—			6
Total before tax		$	(1	)	$	6

Income Tax (Tables)

3 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Effective Tax Rate

	Three Months Ended December 31
	2021			2020
	(Dollars in millions)
(Provision) benefit for income taxes	$	12		$	(29	)
Effective tax rate		13	%		29	%

Earnings Per Share (Tables)

3 Months Ended

Dec. 31, 2021

Earnings Per Share [Abstract]

Components of Basic and Diluted Earnings (Loss) Per Common Share (EPS)

The following tables summarize the components of the basic and diluted earnings (loss) per common share (“EPS”) computations:

	Three Months Ended December 31
	2021			2020
	(In millions, except per share amounts)
Basic EPS:
Net income (loss) attributable to Cabot Corporation	$	(89	)	$	60
Less: Dividends and dividend equivalents to participating securities		—			—
Less: Undistributed earnings allocated to participating securities⁽¹⁾		—			—
Earnings (loss) allocated to common shareholders (numerator)	$	(89	)	$	60

Weighted average common shares and participating securities outstanding		57.7			57.2
Less: Participating securities⁽¹⁾		0.9			0.7
Adjusted weighted average common shares (denominator)		56.8			56.5

Earnings (loss) per common share - basic:	$	(1.57	)	$	1.06

Diluted EPS:
Earnings (loss) allocated to common shareholders	$	(89	)	$	60
Plus: Earnings allocated to participating securities		—			—
Less: Adjusted earnings allocated to participating securities⁽²⁾		—			—
Earnings (loss) allocated to common shareholders (numerator)	$	(89	)	$	60

Adjusted weighted average common shares outstanding		56.8			56.5
Effect of dilutive securities:
Common shares issuable⁽³⁾		—			0.1
Adjusted weighted average common shares (denominator)		56.8			56.6

Earnings (loss) per common share - diluted:	$	(1.57	)	$	1.06

⁽¹⁾

Calculation of Undistributed Earnings

	Three Months Ended December 31
	2021			2020
	(In millions)
Calculation of undistributed earnings (loss):
Net income (loss) attributable to Cabot Corporation	$	(89	)	$	60
Less: Dividends declared on common stock		21			20
Less: Dividends declared on participating securities		—			—
Undistributed earnings (loss)	$	(110	)	$	40

Allocation of undistributed earnings (loss):
Undistributed earnings (loss) allocated to common shareholders	$	(110	)	$	40
Undistributed earnings allocated to participating shareholders		—			—
Undistributed earnings (loss)	$	(110	)	$	40

⁽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⁾

Restructuring (Tables)

3 Months Ended

Dec. 31, 2021

Restructuring And Related Activities [Abstract]

Recorded Restructuring Activities

Cabot’s restructuring activities were recorded in the Consolidated Statements of Operations in the three months ended December 31, 2021 and 2020 as follows:

	Three Months Ended December 31
	2021		2020
	(In millions)
Cost of sales	$	1	$	3
Selling and administrative expenses		1		—
Total	$	2	$	3

Restructuring Activities and Related Reserves

Details of all restructuring activities and the related reserves during the three months ended December 31, 2021 were as follows:

	Severance and Employee Benefits			Environmental Remediation		Total
	(In millions)
Reserve at September 30, 2021	$	5		$	4	$	9
Charges (gain)		2			—		2
Cash paid		(2	)		—		(2	)
Reserve at December 31, 2021	$	5		$	4	$	9

Derivatives (Tables)

3 Months Ended

Dec. 31, 2021

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Details of Derivatives Held to Manage Foreign Currency Risk

The following table provides details of the derivatives held as of December 31, 2021 and September 30, 2021 to manage foreign currency risk.

		Notional Amount
Description	Borrowing	December 31, 2021	September 30, 2021	Hedge Designation
Cross-Currency Swaps	3.4% Notes	USD 250 million swapped to EUR 223 million	USD 250 million swapped to EUR 223 million	Net investment
Forward Foreign Currency Contracts ⁽¹⁾	N/A	USD 36 million	USD 48 million	No designation

⁽¹⁾	^{As of both December 31, 2021 and September 30, 2021, Cabot’s forward foreign exchange contracts were denominated in Indonesian rupiah and Czech koruna and the fair value of these derivative instruments were a nominal amount.}

Summary Impact of Cross-currency Swaps to AOCI and Consolidated Statements of Operations

The following table summarizes the impact of the cross-currency swaps to AOCI and the Consolidated Statements of Operations:

	Three Months Ended December 31
	2021		2020			2021			2020			2021		2020
Description	Gain/(Loss) Recognized in AOCI					(Gain)/Loss Reclassified from AOCI into Interest Expense in the Consolidated Statements of Operations						(Gain)/Loss Recognized in Interest Expense in the Consolidated Statements of Operations (Amount Excluded from Effectiveness Testing)
	(In millions)
Cross-currency swaps	$	—	$	(13	)	$	(1	)	$	(1	)	$	—	$	—

- Definition

Tabular disclosure of pertinent information about a derivative or group of derivatives on a disaggregated basis, such as for individual instruments, or small groups of similar instruments. May include a combination of the type of instrument, risks being hedged, notional amount, hedge designation, related hedged item, inception date, maturity date, or other relevant item.

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+ Details

Financial Information by Segment (Tables)

3 Months Ended

Dec. 31, 2021

Segment Reporting [Abstract]

Schedule of Performance Segment

The net sales from each of these businesses for the three months ended December 31, 2021 and 2020 were as follows:

	Three Months Ended December 31
	2021		2020
	(In millions)
Performance Additives	$	227	$	184
Formulated Solutions		75		83
Total Performance Chemicals	$	302	$	267

Financial Information by Reportable Segment

Financial information by reportable segment is as follows:

	Reinforcement Materials		Performance Chemicals		Purification Solutions			Segment Total		Unallocated and Other⁽¹⁾			Consolidated Total
	(In millions)
Three Months Ended December 31, 2021
Revenues from external customers⁽²⁾	$	541	$	302	$	61		$	904	$	64		$	968
Income (loss) before income taxes⁽³⁾	$	85	$	52	$	—		$	137	$	(230	)	$	(93	)

Three Months Ended December 31, 2020
Revenues from external customers⁽²⁾	$	375	$	267	$	59		$	701	$	45		$	746
Income (loss) before income taxes⁽³⁾	$	88	$	54	$	(2	)	$	140	$	(41	)	$	99

⁽¹⁾	^{Unallocated and Other includes certain items and eliminations necessary to reflect management’s reporting of operating segment results. These items are reflective of the segment reporting presented to the CODM.}

⁽²⁾

	Three Months Ended December 31
	2021			2020
	(In millions)
Shipping and handling fees	$	39		$	33
By-product sales		28			17
Other		(3	)		(5	)
Total	$	64		$	45

⁽³⁾	Consolidated Total Income (loss) before income taxes reconciles to Income (loss) before income taxes and equity in earnings of affiliated companies on the Consolidated Statements of Operations. Income (loss) before income taxes that are categorized as Unallocated and Other includes:

	Three Months Ended December 31
	2021			2020
	(In millions)
Interest expense	$	(12	)	$	(12	)
Certain items^(a)
Purification Solutions assets held for sale impairment charge (Note D)		(197	)		—
Divestiture related charges		(4	)		—
Global restructuring activities (Note K)		(2	)		(3	)
Legal and environmental matters and reserves		(1	)		—
Acquisition and integration-related charges		(1	)		(1	)
Employee benefit plan settlement and other charges		—			(6	)
Other		1			(1	)
Total certain items, pre-tax		(204	)		(11	)
Unallocated corporate costs^(b)		(14	)		(13	)
General unallocated income (expense)^(c)		1			(5	)
Less: Equity in earnings of affiliated companies, net of tax^(d)		1			—
Total	$	(230	)	$	(41	)

^(a)

^(b)

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

^(c)

^(d)

Revenues from External Customers by Geographic Region

	Three Months Ended December 31, 2021
	Reinforcement Materials		Performance Chemicals		Purification Solutions		Consolidated Total
	(In millions)
Americas	$	206	$	90	$	27	$	323
Asia Pacific		240		136		8		384
Europe, Middle East and Africa		95		76		26		197
Segment revenues from external customers		541		302		61		904
Unallocated and other								64
Net sales and other operating revenues							$	968

	Three Months Ended December 31, 2020
	Reinforcement Materials		Performance Chemicals		Purification Solutions		Consolidated Total
	(In millions)
Americas	$	149	$	69	$	25	$	243
Asia Pacific		155		118		9		282
Europe, Middle East and Africa		71		80		25		176
Segment revenues from external customers		375		267		59		701
Unallocated and other								45
Net sales and other operating revenues							$	746

Acquisitions - Additional Information (Detail) $ in Millions	1 Months Ended
	Nov. 30, 2021 USD ($)
Tokai Carbon Group(Tianjin) Co. [Member]
Business Acquisition [Line Items]
Business acquisition, purchase price	$ 9

Divestiture - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended
	Nov. 30, 2021	Dec. 31, 2021
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Impairment charge		$ 197
Purification Solutions [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Disposal value for the sale of business	$ 111
Proceeds from sale of business	$ 80
Impairment charge		197
Impairment charge after tax		160
Marshall Mine \| ADA Carbon Solutions, LLC [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Accounts payable and accrued liabilities		$ 11

Divestiture - Summary of Major Classes of Assets and Liabilities of the Business Classified as Held for Sale (Detail) $ in Millions	Dec. 31, 2021 USD ($)
Assets
Accounts and notes receivable, net of reserve for doubtful accounts	$ 37
Inventories	67
Prepaid expenses and other current assets	2
Property, plant and equipment, net	106
Equity affiliates	28
Intangible assets, net	27
Deferred income taxes	31
Other assets	10
Total assets held for sale	308
Impairment of assets held for sale	(197)
Adjusted assets held for sale	111
Liabilities
Short-term borrowings	(2)
Accounts payable and accrued liabilities	(51)
Income taxes payable	(1)
Long-term debt	(17)
Total liabilities assumed	(71)
Total net assets held for sale	$ 40

Employee Benefit Plans - Net Periodic Defined Benefit Pension Costs (Detail) - Pension Benefits [Member] - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 1
Interest cost	1	1
Expected return on plan assets	$ (2)	(2)
Amortization of actuarial loss		1
Settlement charge		6
Net periodic benefit (credit) cost		$ 7

Employee Benefit Plans - Net Periodic Defined Benefit Pension Costs (Parenthetical) (Detail) - U.S. Defined Benefit Plans [Member] $ in Millions	3 Months Ended
	Dec. 31, 2020 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Settlement charge	$ 6
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Settlement Gain (Loss), Statement of Income or Comprehensive Income [Extensible List]	Other income (expense)

Employee Benefit Plans - Additional Information (Detail) - USD ($)	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Other postretirement benefit costs (gains)	$ 1,000,000	$ 1,000,000

Goodwill and Intangible Assets - Schedule of Goodwill Balances (Detail) $ in Millions	Dec. 31, 2021 USD ($)
Goodwill And Intangible Assets [Line Items]
Beginning balance	$ 140
Ending balance	140
Reinforcement Materials [Member]
Goodwill And Intangible Assets [Line Items]
Beginning balance	48
Ending balance	48
Performance Chemicals [Member]
Goodwill And Intangible Assets [Line Items]
Beginning balance	92
Ending balance	$ 92

Goodwill and Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($)
$ in Millions

Dec. 31, 2021

Sep. 30, 2021

Finite Lived Intangible Assets [Line Items]

Gross Carrying Value, finite lives

$ 98

$ 133

Accumulated Amortization

(28)

(33)

Net Intangible Assets, finite lives

100

Developed Technologies [Member]

Finite Lived Intangible Assets [Line Items]

Gross Carrying Value, finite lives

^[1]

Accumulated Amortization

^[1]

(7)

(12)

Net Intangible Assets, finite lives

^[1]

Trademarks [Member]

Finite Lived Intangible Assets [Line Items]

Gross Carrying Value, finite lives

^[1]

Accumulated Amortization

^[1]

(1)

Net Intangible Assets, finite lives

^[1]

Customer Relationships [Member]

Finite Lived Intangible Assets [Line Items]

Gross Carrying Value, finite lives

Accumulated Amortization

(21)

(20)

Net Intangible Assets, finite lives

$ 39

$ 40

[1]

Goodwill and Intangible Assets - Schedule of Intangible Assets (Parenthetical) (Detail) - USD ($)
$ in Millions

Dec. 31, 2021

Sep. 30, 2021

Finite Lived Intangible Assets [Line Items]

Carrying value of intangible assets

$ 98

$ 133

Accumulated amortization of intangible assets

Developed Technologies [Member]

Finite Lived Intangible Assets [Line Items]

Carrying value of intangible assets

^[1]

Accumulated amortization of intangible assets

^[1]

Developed Technologies [Member] | Purification Solutions [Member]

Finite Lived Intangible Assets [Line Items]

Carrying value of intangible assets

Accumulated amortization of intangible assets

Trademarks [Member]

Finite Lived Intangible Assets [Line Items]

Carrying value of intangible assets

^[1]

Accumulated amortization of intangible assets

^[1]

$ 1

Trademarks [Member] | Purification Solutions [Member]

Finite Lived Intangible Assets [Line Items]

Carrying value of intangible assets

Accumulated amortization of intangible assets

$ 1

[1]

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Goodwill And Intangible Assets [Line Items]
Amortization expense estimated for year one	$ 6
Amortization expense estimated for year two	6
Amortization expense estimated for year three	6
Amortization expense estimated for year four	6
Amortization expense estimated for year five	6
Cost of Sales, Selling and Administrative Expenses and Research and Technical Expenses [Member]
Goodwill And Intangible Assets [Line Items]
Amortization of intangible assets	$ 2	$ 2
Minimum [Member]
Goodwill And Intangible Assets [Line Items]
Useful life of intangible assets	10 years
Maximum [Member]
Goodwill And Intangible Assets [Line Items]
Useful life of intangible assets	25 years
Weighted Average [Member]
Goodwill And Intangible Assets [Line Items]
Useful life of intangible assets	17 years

Accumulated Other Comprehensive Income (Loss) ("AOCI") - Changes in Each Component of AOCI, Net of Tax (Detail) $ in Millions	3 Months Ended
	Dec. 31, 2021 USD ($)
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	$ 1,090
Ending Balance	948
Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(265)
Other comprehensive income (loss) before reclassifications	(28)
Amounts reclassified from AOCI	(1)
Less: Other comprehensive income (loss) attributable to noncontrolling interests	2
Ending Balance	(296)
Pension and Other Postretirement Benefit Liability Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(24)
Other comprehensive income (loss) before reclassifications	1
Ending Balance	(23)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(289)
Other comprehensive income (loss) before reclassifications	(27)
Amounts reclassified from AOCI	(1)
Less: Other comprehensive income (loss) attributable to noncontrolling interests	2
Ending Balance	$ (319)

- Definition

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Accumulated Other Comprehensive Income (Loss) ("AOCI") - Amounts Reclassified Out of AOCI (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
(Gains) Losses Reclassified to Interest Expense [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	$ (1)	$ (1)
Amortization of Actuarial Losses and Prior Service Cost (Credit) [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax		1
Settlement Charge [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax		6
Accumulated Other Comprehensive Income (Loss) [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	$ (1)	$ 6

Contingencies - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021
Pepinster, Belgium [Member] \| Flood [Member]
Loss Contingencies [Line Items]
Flood-related expenses	$ 5	$ 17
Insurance proceeds	5	8
Insurance settlements receivable	9	9
Respirator Liabilities [Member]
Loss Contingencies [Line Items]
Respirator reserve	$ 44	$ 44

Income Tax - Effective Tax Rate (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
(Provision) benefit for income taxes	$ 12	$ (29)
Effective tax rate	13.00%	29.00%

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Income Tax - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Taxes [Line Items]
Net discrete tax (benefits) expense related to tax settlements	$ (37)	$ 2
Uncertain tax positions from expirations of statute of limitations	$ 1	$ 1
Earliest Tax Year [Member] \| United States Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2018
Latest Tax Year [Member] \| United States Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2020
State Tax Authorities [Member] \| Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2005
State Tax Authorities [Member] \| Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2020
Non-U.S. Jurisdictions [Member] \| Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2005
Non-U.S. Jurisdictions [Member] \| Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2020

Earnings Per Share - Components of Basic and Diluted Earnings (Loss) Per Common Share (EPS) (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Basic EPS:
Net income (loss) attributable to Cabot Corporation	$ (89)	$ 60
Earnings (loss) allocated to common shareholders (numerator)	$ (89)	$ 60
Weighted average common shares and participating securities outstanding	57.7	57.2
Less: Participating securities	0.9	0.7
Adjusted weighted average common shares (denominator)	56.8	56.5
Earnings (loss) per common share - basic:	$ (1.57)	$ 1.06
Diluted EPS:
Earnings (loss) allocated to common shareholders	$ (89)	$ 60
Earnings (loss) allocated to common shareholders (numerator)	$ (89)	$ 60
Adjusted weighted average common shares outstanding	56.8	56.5
Common shares issuable		0.1
Adjusted weighted average common shares (denominator)	56.8	56.6
Earnings (loss) per common share - diluted:	$ (1.57)	$ 1.06

Earnings Per Share - Calculation of Undistributed Earnings (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Earnings Per Share [Abstract]
Net income (loss) attributable to Cabot Corporation	$ (89)	$ 60
Less: Dividends declared on common stock	21	20
Undistributed earnings (loss)	(110)	40
Undistributed earnings (loss) allocated to common shareholders	$ (110)	$ 40

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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+ Details

Earnings Per Share - Components of Basic and Diluted Earnings (Loss) Per Common Share (EPS) (Parenthetical) (Detail) - shares	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Earnings Per Share [Abstract]
Antidilutive securities excluded from computation of earnings per share	2,356,941	1,305,993

Restructuring - Recorded Restructuring Activities (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Restructuring Cost And Reserve [Line Items]
Restructuring reserve, period expense	$ 2	$ 3
Cost of Sales [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring reserve, period expense	1	$ 3
Selling and Administrative Expenses [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring reserve, period expense	$ 1

Restructuring - Restructuring Activities and Related Reserves (Detail) $ in Millions	3 Months Ended
	Dec. 31, 2021 USD ($)
Restructuring Cost And Reserve [Line Items]
Reserve balance	$ 9
Charges (gain)	2
Cash paid	(2)
Reserve balance	9
Severance and Employee Benefits [Member]
Restructuring Cost And Reserve [Line Items]
Reserve balance	5
Charges (gain)	2
Cash paid	(2)
Reserve balance	5
Environmental Remediation [Member]
Restructuring Cost And Reserve [Line Items]
Reserve balance	4
Reserve balance	$ 4

Restructuring - Additional Information (Detail) - Reorganization Actions [Member] - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021
Restructuring Cost And Reserve [Line Items]
Severance costs	$ 24	$ 22
Accrued severance charges	4
Restructuring charges expected throughout rest of 2022 related to site demolition costs	1
Restructuring charges expected thereafter fiscal year related to severance and site demolition costs	2
Restructuring cash payments of fiscal year	19	$ 18
Restructuring cash payments through the reminder of fiscal 2022	4
Restructuring future cash payments thereafter fiscal year	$ 3

Financial Instruments and Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Sep. 30, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, liabilities, Level 2 to Level 1 transfers, amount	$ 0	$ 0
Fair value, assets, Level 2 to Level 1 transfers, amount	0	0
Fair value, liabilities, Level 1 to Level 2 transfers, amount	0	0
Fair value, assets, Level 1 to Level 2 transfers, amount	0	0
Fair value, assets, transfers into Level 3, amount	0	0
Fair value, assets, transfers out of Level 3, amount	0	0
Fair value, liabilities, transfers into Level 3, amount	0	0
Fair value, liabilities, transfers out of Level 3, amount	0	$ 0
Fair value of long-term debt	1,120,000,000		$ 1,130,000,000
Fixed Rate Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value of long-term debt	1,060,000,000.00		1,060,000,000.00
Significant Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets in the Consolidated Balance Sheets	10,000,000		10,000,000
Significant Observable Inputs (Level 2) [Member] \| Foreign Currency Risks [Member] \| Prepaid Expenses and Other Current Assets and Other Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets (liabilities), at fair Value, net	$ 3,000,000
Significant Observable Inputs (Level 2) [Member] \| Foreign Currency Risks [Member] \| Prepaid Expenses and Other Current Assets Accounts Payable and Accrued Liabilities and Other Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets (liabilities), at fair Value, net			$ 3,000,000

Derivatives - Details of Derivatives Held to Manage Foreign Currency Risk (Detail)

Dec. 31, 2021

USD ($)

Dec. 31, 2021

EUR (€)

Sep. 30, 2021

USD ($)

Sep. 30, 2021

EUR (€)

Net Investment Hedge [Member] | Cross Currency Swaps [Member]

Derivative [Line Items]

Notional Amount

$ 250,000,000

Net Investment Hedge [Member] | 3.4% Notes [Member] | Cross Currency Swaps [Member]

Derivative [Line Items]

Notional Amount

$ 250,000,000

€ 223,000,000

$ 250,000,000

€ 223,000,000

Net Investment Hedge [Member] | 3.4% Notes [Member] | Fixed Rate Debt [Member] | Cross Currency Swaps [Member]

Derivative [Line Items]

Interest rate on borrowing

3.40%

Not Designated as Hedging Instrument [Member] | Forward Foreign Currency Contracts [Member]

Derivative [Line Items]

Notional Amount

^[1]

$ 36,000,000

$ 48,000,000

[1]	As of both December 31, 2021 and September 30, 2021, Cabot’s forward foreign exchange contracts were denominated in Indonesian rupiah and Czech koruna and the fair value of these derivative instruments were a nominal amount.

Derivatives - Additional Information (Detail) - Cross Currency Swaps [Member] - USD ($)	3 Months Ended
	Dec. 31, 2021	Sep. 30, 2021
Derivative [Line Items]
Fair value of swaps, net assets	$ 3,000,000
Fair value of swaps, net liability		$ 3,000,000
Net Investment Hedge [Member]
Derivative [Line Items]
Notional Amount	250,000,000
Cumulative gain (loss) related to swaps	$ 5,000,000	$ 6,000,000
Net Investment Hedge [Member] \| Fixed Rate Debt [Member]
Derivative [Line Items]
Derivative Instruments Frequency of Cash Settlements	semi-annually

Derivatives - Summary Impact of Cross-currency Swaps to AOCI and Consolidated Statements of Operations (Detail) - Cross Currency Swaps [Member] - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Derivative Instruments Gain Loss [Line Items]
Gain/(Loss) Recognized in AOCI		$ (13)
(Gain)/Loss Reclassified from AOCI into Interest Expense in the Consolidated Statements of Operations	$ (1)	$ (1)

Financial Information by Segment - Additional Information (Detail) - Segment	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Number of business reportable segments		3
Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Number of business reportable segments		1
Scenario, Forecast [Member]
Segment Reporting Information [Line Items]
Number of business reportable segments	2

Financial Information by Segment - Schedule of Performance Segment (Detail) - Performance Chemicals [Member] - Operating Segments [Member] - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Net sales	$ 302	$ 267
Performance Additives [Member]
Segment Reporting Information [Line Items]
Net sales	227	184
Formulated Solutions [Member]
Segment Reporting Information [Line Items]
Net sales	$ 75	$ 83

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

Financial Information by Segment - Financial Information by Reportable Segment (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Revenues from external customers	$ 968	$ 746
Income (loss) before income taxes	(93)	99
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	904	701
Income (loss) before income taxes	137	140
Unallocated and Other [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	64	45
Income (loss) before income taxes	(230)	(41)
Reinforcement Materials [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	541	375
Income (loss) before income taxes	85	88
Performance Chemicals [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	302	267
Income (loss) before income taxes	52	54
Purification Solutions [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	$ 61	59
Income (loss) before income taxes		$ (2)

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 235
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-URI http://asc.fasb.org/extlink&oid=120399901&loc=d3e537907-122884

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(B))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756

Reference 22: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(ii))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442526-122756

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1))
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

+ Details

Financial Information by Segment - Financial Information by Reportable Segment (Parenthetical) (Detail)	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting [Abstract]
Percentage of sale of an equity method affiliate	100.00%	100.00%

Financial Information by Segment - Sales of Equity Method Affiliate and Discounting Charges for Certain Notes Receivable, by-product Revenue and Indirect Tax Settlement Credits (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Revenues from external customers	$ 968	$ 746
Unallocated and Other [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	64	45
Unallocated and Other [Member] \| Shipping and Handling Costs [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	39	33
Unallocated and Other [Member] \| By-product Sales [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	28	17
Unallocated and Other [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	$ (3)	$ (5)

- Definition

+ References

+ Details

Financial Information by Segment - Schedule of Income (Loss) from Continuing Operations before Income Taxes and Equity in Earnings of Affiliated Companies for Unallocated and Other (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Interest expense	$ (12)	$ (12)
Purification Solutions assets held for sale impairment charge (Note D)	(197)
Global restructuring activities	(2)	(3)
Unallocated and Other [Member]
Segment Reporting Information [Line Items]
Interest expense	(12)	(12)
Unallocated corporate costs	(14)	(13)
General unallocated income (expense)	1	(5)
Less: Equity in earnings of affiliated companies, net of tax	1
Income from continuing operations before income taxes and equity in earnings of affiliated companies	(230)	(41)
Certain Items [Member]
Segment Reporting Information [Line Items]
Purification Solutions assets held for sale impairment charge (Note D)	(197)
Divestiture related charges	(4)
Global restructuring activities	(2)	(3)
Legal and environmental matters and reserves	(1)
Acquisition and integration-related charges	(1)	(1)
Employee benefit plan settlement and other charges		(6)
Other	1	(1)
Total certain items, pre-tax	$ (204)	$ (11)

Financial Information by Segment - Revenue from External Customers by Geographic Region (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Net sales and other operating revenues	$ 968	$ 746
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	904	701
Unallocated and Other [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	64	45
Americas [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	323	243
Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	384	282
Europe, Middle East and Africa [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	197	176
Reinforcement Materials [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	541	375
Reinforcement Materials [Member] \| Americas [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	206	149
Reinforcement Materials [Member] \| Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	240	155
Reinforcement Materials [Member] \| Europe, Middle East and Africa [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	95	71
Performance Chemicals [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	302	267
Performance Chemicals [Member] \| Americas [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	90	69
Performance Chemicals [Member] \| Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	136	118
Performance Chemicals [Member] \| Europe, Middle East and Africa [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	76	80
Purification Solutions [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	61	59
Purification Solutions [Member] \| Americas [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	27	25
Purification Solutions [Member] \| Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	8	9
Purification Solutions [Member] \| Europe, Middle East and Africa [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	$ 26	$ 25