Cabot (CBT) 10-Q 9 May 23 2023 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Mar. 31, 2023	May 04, 2023
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
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		56,146,458
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 Oper

Consolidated Statements of Operations (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Income Statement [Abstract]
Net sales and other operating revenues	$ 1,033	$ 1,092	$ 1,998	$ 2,060
Cost of sales	823	860	1,607	1,630
Gross profit	210	232	391	430
Selling and administrative expenses	66	74	126	145
Research and technical expenses	15	14	28	27
Loss on sale of business and asset impairment charge (Note D)		7	3	204
Gain on bargain purchase of a business (Note C)		(24)		(24)
Income (loss) from operations	129	161	234	78
Interest and dividend income	9	4	15	7
Interest expense	(23)	(11)	(45)	(23)
Other income (expense)	(5)	(7)	(10)	(8)
Income (loss) before income taxes and equity in earnings of affiliated companies	110	147	194	54
(Provision) benefit for income taxes	(29)	(36)	(49)	(24)
Equity in earnings of affiliated companies, net of tax	1	3	3	4
Net income (loss)	82	114	148	34
Net income (loss) attributable to noncontrolling interests, net of tax	7	7	19	16
Net income (loss) attributable to Cabot Corporation	$ 75	$ 107	$ 129	$ 18
Weighted-average common shares outstanding:
Basic	56.3	56.6	56.3	56.5
Diluted	56.8	57.1	56.7	56.9
Earnings (loss) per common share:
Basic	$ 1.31	$ 1.86	$ 2.24	$ 0.30
Diluted	$ 1.29	$ 1.84	$ 2.23	$ 0.30

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 82	$ 114	$ 148	$ 34
Other comprehensive income (loss), net of tax
Foreign currency translation adjustment, net of tax	49	46	137	18
Derivatives: net investment hedges
(Gains) losses reclassified to interest expense, net of tax	(2)	(2)	(3)	(3)
(Gains) losses excluded from effectiveness testing and amortized to interest expense, net of tax	1	1	1	1
Pension and other postretirement benefit liability adjustments, net of tax	(1)	1	(1)	2
Other comprehensive income (loss), net of tax of $ - , $ - , $ - and $(1)	47	46	134	18
Comprehensive income (loss)	129	160	282	52
Net income (loss) attributable to noncontrolling interests, net of tax	7	7	19	16
Foreign currency translation adjustment attributable to noncontrolling interests, net of tax	3	1	9	3
Comprehensive income (loss) attributable to noncontrolling interests	10	8	28	19
Comprehensive income (loss) attributable to Cabot Corporation	$ 119	$ 152	$ 254	$ 33

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (Parenthetical) $ in Millions	6 Months Ended
	Mar. 31, 2022 USD ($)
Statement Of Income And Comprehensive Income [Abstract]
Net of tax	$ (1)

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Mar. 31, 2023	Sep. 30, 2022
Current assets:
Cash and cash equivalents	$ 205	$ 206
Accounts and notes receivable, net of reserve for doubtful accounts of $3 and $3	767	836
Inventories:
Raw materials	161	182
Finished goods	397	427
Other	67	55
Total inventories	625	664
Prepaid expenses and other current assets	145	114
Total current assets	1,742	1,820
Property, plant and equipment, net	1,353	1,270
Goodwill	136	129
Equity affiliates	22	20
Intangible assets, net	63	63
Deferred income taxes	38	45
Other assets	165	178
Total assets	3,519	3,525
Current liabilities:
Short-term borrowings	258	347
Accounts payable and accrued liabilities	609	707
Income taxes payable	29	44
Current portion of long-term debt	8	7
Total current liabilities	904	1,105
Long-term debt	1,094	1,089
Deferred income taxes	58	65
Other liabilities	231	234
Contingencies (Note G)
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: 56,282,299 and 56,385,963 shares, Outstanding: 56,146,164 and 56,248,559 shares	56	56
Less cost of 136,135 and 137,404 shares of common treasury stock	(3)	(4)
Additional paid-in capital		1
Retained earnings	1,360	1,284
Accumulated other comprehensive income (loss)	(314)	(439)
Total Cabot Corporation stockholders' equity	1,099	898
Noncontrolling interests	133	134
Total stockholders' equity	1,232	1,032
Total liabilities and stockholders' equity	$ 3,519	$ 3,525

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) (Unaudited) - USD ($) $ in Millions	Mar. 31, 2023	Sep. 30, 2022
Statement Of Financial Position [Abstract]
Accounts and notes receivable, reserve for doubtful accounts	$ 3	$ 3
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	56,282,299	56,385,963
Common stock, outstanding shares	56,146,164	56,248,559
Common treasury stock, shares	136,135	137,404

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash Flows from Operating Activities:
Net income (loss)	$ 148	$ 34
Adjustments to reconcile net income (loss) to cash provided (used) by operating activities:
Depreciation and amortization	71	75
Loss on sale of business and asset impairment charge	3	204
Gain on sale of land	(1)
Gain on bargain purchase of a business		(24)
Deferred tax provision (benefit)	(3)	(45)
Equity in earnings of affiliated companies	(3)	(4)
Share-based compensation	12	11
Other non-cash (income) expense	(2)	8
Cash dividends received from equity affiliates	2
Changes in assets and liabilities:
Accounts and notes receivable	108	(161)
Inventories	72	(177)
Prepaid expenses and other assets	(25)	(55)
Accounts payable and accrued liabilities	(155)	84
Income taxes payable	(16)	10
Other liabilities	3	1
Cash provided (used) by operating activities	214	(39)
Cash Flows from Investing Activities:
Additions to property, plant and equipment	(86)	(71)
Proceeds from sale of land	7
Proceeds from sale of business	6	79
Cash assumed from acquisition of a business		5
Other	9	2
Cash provided (used) by investing activities	(64)	15
Cash Flows from Financing Activities:
Proceeds from short-term borrowings	14	13
Proceeds from issuance (repayments) of commercial paper, net	(105)	167
Repayments of long-term debt	(7)	(7)
Purchases of common stock	(33)	(34)
Proceeds from sales of common stock	4	3
Cash dividends paid to noncontrolling interests	(41)	(15)
Cash dividends paid to common stockholders	(42)	(42)
Cash provided (used) by financing activities	(210)	85
Effects of exchange rate changes on cash	59	(16)
Increase (decrease) in cash and cash equivalents	(1)	45
Cash and cash equivalents at beginning of period	206	170
Cash and cash equivalents at end of period	$ 205	$ 215

Consolidated Statements of Chan

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, 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
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
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)	34
Total other comprehensive income (loss)	18
Ending Balance at Mar. 31, 2022	1,066	$ 53	4	1,135	(274)	918	148
Ending Balance, Shares at Mar. 31, 2022		56,431
Beginning Balance at Dec. 31, 2021	948	$ 53	11	1,049	(319)	794	154
Beginning Balance, Shares at Dec. 31, 2021		56,580
Net income (loss)	114			107		107	7
Total other comprehensive income (loss)	46				45	45	1
Cash dividends paid, Common stock, per share	(21)			(21)		(21)
Cash dividends declared to noncontrolling interests	(14)						(14)
Issuance of stock under equity compensation plans	3		3			3
Issuance of stock under equity compensation plans, Shares		72
Share-based compensation	5		5			5
Purchase and retirement of common stock	(15)		(15)			(15)
Purchase and retirement of common stock, Shares		(221)
Ending Balance at Mar. 31, 2022	1,066	$ 53	4	1,135	(274)	918	148
Ending Balance, Shares at Mar. 31, 2022		56,431
Beginning Balance at Sep. 30, 2022	1,032	$ 52	1	1,284	(439)	898	134
Beginning Balance, Shares at Sep. 30, 2022		56,249
Net income (loss)	66			54		54	12
Total other comprehensive income (loss)	87				81	81	6
Cash dividends paid, Common stock, per share	(21)			(21)		(21)
Cash dividends declared to noncontrolling interests	(2)						(2)
Issuance of stock under equity compensation plans	3	$ 1	2			3
Issuance of stock under equity compensation plans, Shares		309
Share-based compensation	11		11			11
Purchase and retirement of common stock	(17)		(14)	(3)		(17)
Purchase and retirement of common stock, Shares		(242)
Ending Balance at Dec. 31, 2022	1,159	$ 53		1,314	(358)	1,009	150
Ending Balance, Shares at Dec. 31, 2022		56,316
Beginning Balance at Sep. 30, 2022	1,032	$ 52	1	1,284	(439)	898	134
Beginning Balance, Shares at Sep. 30, 2022		56,249
Net income (loss)	148
Total other comprehensive income (loss)	134
Ending Balance at Mar. 31, 2023	1,232	$ 53		1,360	(314)	1,099	133
Ending Balance, Shares at Mar. 31, 2023		56,146
Beginning Balance at Dec. 31, 2022	1,159	$ 53		1,314	(358)	1,009	150
Beginning Balance, Shares at Dec. 31, 2022		56,316
Net income (loss)	82			75		75	7
Total other comprehensive income (loss)	47				44	44	3
Cash dividends paid, Common stock, per share	(21)			(21)		(21)
Cash dividends declared to noncontrolling interests	(27)						(27)
Issuance of stock under equity compensation plans	1		1			1
Issuance of stock under equity compensation plans, Shares		29
Share-based compensation	7		7			7
Purchase and retirement of common stock	(16)		$ (8)	(8)		(16)
Purchase and retirement of common stock, Shares		199
Ending Balance at Mar. 31, 2023	$ 1,232	$ 53		$ 1,360	$ (314)	$ 1,099	$ 133
Ending Balance, Shares at Mar. 31, 2023		56,146

Consolidated Statements of Ch_2

Consolidated Statements of Changes in Stockholders' Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Statement Of Stockholders Equity [Abstract]
Common stock, cash dividends paid, per share	$ 0.37	$ 0.37	$ 0.37	$ 0.37

Basis of Presentation

Basis of Presentation	6 Months Ended
	Mar. 31, 2023
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, 2022 (“2022 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 March 31, 2023 and 2022. All such adjustments are of a normal rec urring nature. The results for interim periods are not necessarily indicative of the results to be expected for the fiscal year.

Significant Accounting Policies

Significant Accounting Policies	6 Months Ended
	Mar. 31, 2023
Accounting Policies [Abstract]
Significant Accounting Policies	B. Significant Accounting Policies Recent Accounting Pronouncements In August 2022, the U.S. government enacted the Inflation Reduction Act ("IRA") which, among other things, provides for a 1 % excise tax on stock repurchases. The IRA was effective January 1, 2023. The Company’s application of the statute did not have a material effect on its Consolidated Financial Statements, or its share repurchase program. In November 2022, the FASB issued a new standard on the disclosure of supplier financing programs. The new standard requires qualitative and quantitative disclosure as to the nature and potential magnitude of such programs in addition to program activity and changes for the periods presented. The standard is effective for fiscal years beginning after December 15, 2022 and early adoption is permitted. The Company is currently evaluating the timing of adoption and the impact of the adoption of this standard on its Consolidated Financial Statements.

Acquisition

Acquisition	6 Months Ended
	Mar. 31, 2023
Business Combinations [Abstract]
Acquisition	C. Acquisition Tokai Carbon (Tianjin) Co. In February 2022, the Company purchased 100 % of the registered capital of Tokai Carbon (Tianjin) Co., a carbon black manufacturing facility, from Tokai Carbon Group for a net purchase price of $ 9 million, consisting of cash consideration of $ 14 million, including customary post-closing adjustments, and net of $ 5 million of cash acquired. The excess of the fair value of the net assets over the purchase price was recorded as a gain of $ 24 million for the three months ended March 31, 2022. The Gain on bargain purchase of a business arose primarily due to equipment upgrades required after the purchase to continue to utilize the existing assets.

Divestitures

Divestitures	6 Months Ended
	Mar. 31, 2023
Discontinued Operations And Disposal Groups [Abstract]
Divestitures	D. Divestitures Sale of Purification Solutions Business In March 2022, the Company completed the sale of its Purification Solutions business, a reporting segment of the Company, to an affiliate of funds advised by One Equity Partners for total cash proceeds of $ 85 million, net of $ 7 million cash transferred. The Company recognized a pre-tax impairment charge of $ 197 million during the first quarter of fiscal 2022 and a pre-tax loss on sale of the Purification Solutions business of $ 10 million during fiscal 2022. The purchase price of the Purification Solutions business was subject to customary post-closing adjustments, which were finalized during the first quarter of fiscal 2023 and resulted in an additional pre-tax loss on sale of $ 3 million.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	6 Months Ended
	Mar. 31, 2023
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	E. Goodwill and Intangible Assets The carrying amount of goodwill attributable to each reportable segment and the changes in those balances during the six months ended March 31, 2023 are as follows: Reinforcement Performance Total (In millions) Balance at September 30, 2022 $ 46 $ 83 $ 129 Foreign currency impact 4 3 7 Balance at March 31, 2023 $ 50 $ 86 $ 136 The following table provides information regarding the Company’s intangible assets: March 31, 2023 September 30, 2022 Gross Accumulated Net Gross Accumulated Net (In millions) Intangible assets with finite lives Developed technologies $ 34 $ ( 9 ) 25 $ 34 $ ( 8 ) $ 26 Trademarks 2 ( 1 ) 1 2 ( 1 ) 1 Customer relationships 64 ( 27 ) 37 59 ( 23 ) 36 Total intangible assets $ 100 $ ( 37 ) $ 63 $ 95 $ ( 32 ) $ 63 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 and $ 1 million for the three months ended March 31, 2023 and 2022, respectively. Amortization expense for each of the six months ended March 31, 2023 and 2022 was $ 3 million. Amortization expense 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 m illion each year for the next five fiscal years.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss) ("AOCI")	6 Months Ended
	Mar. 31, 2023
Stockholders Equity Note [Abstract]
Accumulated Other Comprehensive Income (Loss) ("AOCI")	F. 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 Pension and Other Total (In millions) Balance at September 30, 2022, attributable to Cabot Corporation $ ( 429 ) $ ( 10 ) $ ( 439 ) Other comprehensive income (loss) before reclassifications 88 — 88 Amounts reclassified from AOCI ( 1 ) — ( 1 ) Less: Other comprehensive income (loss) attributable to 6 — 6 Balance at December 31, 2022, attributable to Cabot Corporation ( 348 ) ( 10 ) ( 358 ) Other comprehensive income (loss) before reclassifications 49 — 49 Amounts reclassified from AOCI ( 1 ) ( 1 ) ( 2 ) Less: Other comprehensive income (loss) attributable to 3 — 3 Balance at March 31, 2023, attributable to Cabot Corporation $ ( 303 ) $ ( 11 ) $ ( 314 ) The amounts reclassified out of AOCI and into the Consolidated Statements of Operations in each of the three and six months ended March 31, 2023 and 2022 were are follows: Affected Line Item in the Consolidated Three Months Ended March 31 Six Months Ended March 31 Statements of Operations 2023 2022 2023 2022 (In millions) Derivatives: net investment hedges (Gains) losses reclassified to interest expense Interest expense $ ( 2 ) $ ( 2 ) $ ( 3 ) $ ( 3 ) (Gains) losses excluded from effectiveness testing and amortized to interest expense Interest expense 1 1 1 1 Release of currency translation adjustment Loss on sale of business and asset impairment charge — 33 — 33 Pension and other postretirement Release of actuarial losses and prior service cost (credit) Loss on sale of business and asset impairment charge — 1 — 1 Amortization of actuarial losses and prior service cost (credit) Other income (expense) ( 1 ) — ( 1 ) — Total before tax $ ( 2 ) $ 33 $ ( 3 ) $ 32

Contingencies

Contingencies	6 Months Ended
	Mar. 31, 2023
Commitments And Contingencies Disclosure [Abstract]
Contingencies	G. 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 2022 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 2022 10-K, the “Payor Group”). On July 26, 2022, one of the members of the Payor Group, Aearo Technologies (“Aearo”), voluntarily filed for Chapter 11 bankruptcy protection with the stated goal of establishing a trust, funded by Aearo and its parent 3M, to satisfy respirator and other unrelated claims determined to be entitled to compensation. The Company will continue to monitor these proceedings for any impact on its liability for respirator claims. 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 balance was $ 38 million and $ 39 million at March 31, 2023 and September 30, 2022, respectively. 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 and developments in the Aearo bankruptcy proceedings, (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. 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.

Insurance Recoveries

Insurance Recoveries	6 Months Ended
	Mar. 31, 2023
Insurance Recovery [Abstract]
Insurance Recoveries	H. 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, which was temporarily halted, resumed in the second quarter of fiscal 2022. During the three and six months ended March 31, 2023, the Company recorded no additional expenses related to the flood and recorded insurance proceeds of $ 8 million and $ 14 million, respectively. The $ 8 million of insurance proceeds recorded during the second quarter of fiscal 2023 represents final settlement of the claim and was received in April 2023. The $ 6 million of proceeds received during the first quarter of fiscal 2023 is included in Cash provided by investing activities in the Consolidated Statements of Cash Flows. During the three and six months ended March 31, 2023, the Company recognized gains of $ 4 million and $ 9 million and loss recoveries of zero and $ 1 million, respectively, which are included within Cost of sales in the Consolidated Statements of Operations. At March 31, 2023 and September 30, 2022, the receivable for insurance recoveries was $ 8 million and $ 4 million, respectively. During the three and six months ended March 31, 2022, the Company recorded additional expenses of $ 1 million and $ 6 million, respectively, for clean-up costs, inventory, and fixed asset impairments and simultaneously recognized a fully offsetting loss recovery from expected insurance proceeds as the Company expected insurance proceeds in excess of the total incurred costs and policy deductibles. The flood-related expenses and loss recoveries are both included within Cost of sales in the Consolidated Statements of Operations for the three and six months ended March 31, 2022.

Income Tax

Income Tax	6 Months Ended
	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Income Tax	I. Income Tax Effective Tax Rate Three Months Ended March 31 Six Months Ended March 31 2023 2022 2023 2022 (Dollars in millions) (Provision) benefit for income taxes $ ( 29 ) $ ( 36 ) $ ( 49 ) $ ( 24 ) Effective tax rate 26 % 24 % 25 % 44 % For the three months and six months ended March 31, 2023, the (Provision) benefit for income taxes included a net discrete tax benefit of $ 2 million and a net discrete tax expense of $ 1 million, respectively . For the three and six months ended March 31, 2022, the (Provision) benefit for income taxes included a net discrete tax expense of $ 1 million and a net discrete tax benefit of $ 36 million, respectively, after valuation allowance. The $ 36 million benefit is primarily related to the Purification Solutions business divestiture. 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 it is expected that 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 2019 through 2021 tax years generally remain subject to examination by the IRS and various tax years from 2009 through 2021 remain subject to examination by the respective state tax authorities. In foreign jurisdictions, various tax years from 2005 through 2022 remain subject to examination by their respective tax authorities. Duri ng the three and six months ended March 31, 2023, Cabot released uncertain tax positions of less than $ 1 million and $ 1 million, respectively, due to the expiration of statutes of limitations in various jurisdictions. During the three and six months ended March 31, 2022, Cabot released uncertain tax positions of $ 1 million and $ 2 million, respectively, due to the expiration of statutes of limitations in various jurisdictions.

Earnings Per Share

Earnings Per Share	6 Months Ended
	Mar. 31, 2023
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 March 31 Six Months Ended March 31 2023 2022 2023 2022 (In millions, except per share amounts) Basic EPS: Net income (loss) attributable to Cabot $ 75 $ 107 $ 129 $ 18 Less: Dividends and dividend equivalents 1 1 1 1 Less: Undistributed earnings allocated to (1) 1 1 2 — Earnings (loss) allocated to common $ 73 $ 105 $ 126 $ 17 Weighted average common shares and 57.6 57.5 57.6 57.4 Less: Participating securities (1) 1.3 0.9 1.3 0.9 Adjusted weighted average common 56.3 56.6 56.3 56.5 Earnings (loss) per common share - basic: $ 1.31 $ 1.86 $ 2.24 $ 0.30 Diluted EPS: Earnings (loss) allocated to common $ 73 $ 105 $ 126 $ 17 Plus: Earnings allocated to 2 2 3 1 Less: Adjusted earnings allocated to (2) 2 2 3 1 Earnings (loss) allocated to common $ 73 $ 105 $ 126 $ 17 Adjusted weighted average common 56.3 56.6 56.3 56.5 Effect of dilutive securities: Common shares issuable (3) 0.5 0.5 0.4 0.4 Adjusted weighted average common 56.8 57.1 56.7 56.9 Earnings (loss) per common share - diluted: $ 1.29 $ 1.84 $ 2.23 $ 0.30 (1) Participating securities consist of shares underlying unvested time-based restricted stock units (the "TSUs"), earned and unvested performance-based restricted stock units (the "PSUs", and referred to in this note collectively with the TSUs as the "RSUs"), stock units accounted for under the Supplemental 401(k) Plan portion of the Company’s Deferred Compensation and Supplemental Retirement Plan, and stock units and phantom stock units accounted for under the Company’s Non-Employee Directors’ Deferral Plan. The holders of RSUs are entitled to receive dividend equivalents, payable in cash, to the extent dividends are paid on the outstanding shares of Common Stock, and equal in value to the dividends that would have been paid in respect of the Common Stock underlying the RSU. The accounts of holders of stock units and phantom stock units are credited with dividend equivalents, which are payable, in stock or cash, as the case may be, with the distribution of account balances. 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 March 31 Six Months Ended March 31 2023 2022 2023 2022 (In millions) Calculation of undistributed earnings (loss): Net income (loss) attributable to Cabot Corporation $ 75 $ 107 $ 129 $ 18 Less: Dividends declared on common stock 21 21 42 42 Less: Dividends declared on participating 1 1 1 1 Undistributed earnings (loss) $ 53 $ 85 $ 86 $ ( 25 ) Allocation of undistributed earnings (loss): Undistributed earnings (loss) allocated to $ 52 $ 84 $ 84 $ ( 25 ) Undistributed earnings allocated to 1 1 2 — Undistributed earnings (loss) $ 53 $ 85 $ 86 $ ( 25 ) (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 assumed exercise of stock options issued under Cabot’s equity incentive plans. For the three and six months ended March 31, 2023, 156,550 and 121,283 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. For the three and six months ended March 31, 2022, 242,031 and 356,476 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.

Financial Instruments and Fair

Financial Instruments and Fair Value Measurements	6 Months Ended
	Mar. 31, 2023
Fair Value Disclosures [Abstract]
Financial Instruments and Fair Value Measurements	K. 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 six months of either fiscal 2023 or 2022. At March 31, 2023 and September 30, 2022, 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. Each of these financial asset and liability categories is classified as Level 1 within the fair value hierarchy. At March 31, 2023 and September 30, 2022, Cabot had derivatives relating to foreign currency risks, including a net investment hedge and forward foreign currency contracts, carried at fair value. At March 31, 2023, the fair value of these derivatives was a net asset of $ 11 million and was included in Prepaid expenses and other current assets, Accounts payable and accrued liabilities, and Other assets on the Consolidated Balance Sheets. At September 30, 2022, the fair value of these derivatives was a net asset of $ 28 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 March 31, 2023 and September 30, 2022, the fair value of guaranteed investment contracts included in Other assets on the Consolidated Balance Sheets was $ 9 million and $ 8 million, respectively. 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. The carrying value and fair value of the long-term fixed rate debt were $ 1.08 billion and $ 1.09 billion, respectively, as of March 31, 2023 and $ 1.08 billion and $ 1.06 billion, respectively, as of September 30, 2022. 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.

Financial Information by Segmen

Financial Information by Segment	6 Months Ended
	Mar. 31, 2023
Segment Reporting [Abstract]
Financial Information by Segment	L. 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 two reportable segments consisting of Reinforcement Materials and Performance Chemicals. The Company’s former Purification Solutions business was a separate reporting segment prior to divestiture in the second quarter of fiscal 2022. The Reinforcement Materials segment combines the reinforcing carbons and engineered elastomer composites product lines. The Performance Chemicals segment aggregates the specialty carbons, specialty compounds, fumed metal oxides, battery materials, inkjet colorants, and aerogel product lines. 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 Purification Solutions segment consisted 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, 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 Performance Purification Segment Unallocated (1) Consolidated (In millions) Three Months Ended March 31, 2023 Revenues from external customers (3) $ 672 $ 326 $ — $ 998 $ 35 $ 1,033 Income (loss) before income taxes (4) $ 122 $ 28 $ — $ 150 $ ( 40 ) $ 110 Three Months Ended March 31, 2022 Revenues from external customers (2)(3) $ 654 $ 363 $ 36 $ 1,053 $ 39 $ 1,092 Income (loss) before income taxes (4) $ 101 $ 70 $ — $ 171 $ ( 24 ) $ 147 Six Months Ended March 31, 2023 Revenues from external customers (3) $ 1,315 $ 612 $ — $ 1,927 $ 71 $ 1,998 Income (loss) before income taxes (4) $ 216 $ 57 $ — $ 273 $ ( 79 ) $ 194 Six Months Ended March 31, 2022 Revenues from external customers (2)(3) $ 1,217 $ 669 $ 97 $ 1,983 $ 77 $ 2,060 Income (loss) before income taxes (4) $ 186 $ 122 $ — $ 308 $ ( 254 ) $ 54 (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) Beginning in the fiscal year 2023, the Company began allocating energy center by-product revenue within the applicable segment’s Revenue from external customers. The Company recast prior period financial information to conform to the new presentation. The allocation of such revenue resulted in an increase of $ 27 million in the Reinforcement Materials segment and $ 3 million in the Performance Chemicals segment, respectively, with an offsetting decrease in Unallocated and Other revenue for the three months ended March 31, 2022. The allocation of such revenue resulted in an increase of $ 49 million in the Reinforcement Materials segment and $ 7 million in the Performance Chemicals segment, respectively, with an offsetting decrease in Unallocated and Other revenue for the six months ended March 31, 2022. There was no impact to the Consolidated Total Revenues from external customers. (3) 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, discounting charges for certain Notes receivable, and other by-product revenue. Details are provided in the table below: Three Months Ended March 31 Six Months Ended March 31 2023 2022 2023 2022 (In millions) Shipping and handling fees $ 36 $ 41 $ 69 $ 80 Other ( 1 ) ( 2 ) 2 ( 3 ) Total $ 35 $ 39 $ 71 $ 77 (4) 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 March 31 Six Months Ended March 31 2023 2022 2023 2022 (In millions) Interest expense $ ( 23 ) $ ( 11 ) $ ( 45 ) $ ( 23 ) Certain items (a) Gain on bargain purchase of a business (Note C) — 24 — 24 Gain on sale of land — — 1 — Loss on sale of business and asset impairment charge (Note D) — ( 7 ) ( 3 ) ( 204 ) Legal and environmental matters and reserves ( 1 ) ( 7 ) ( 2 ) ( 8 ) Acquisition and integration-related charges — ( 2 ) ( 1 ) ( 3 ) Divestiture related charges — ( 1 ) — ( 5 ) Global restructuring activities — — — ( 2 ) Other ( 1 ) — ( 1 ) 1 Total certain items, pre-tax ( 2 ) 7 ( 6 ) ( 197 ) Unallocated corporate costs (b) ( 16 ) ( 16 ) ( 31 ) ( 30 ) General unallocated income (expense) (c) 2 ( 1 ) 6 — Less: Equity in earnings of affiliated companies, net (d) 1 3 3 4 Total $ ( 40 ) $ ( 24 ) $ ( 79 ) $ ( 254 ) (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 and unrealized holding gains (losses) for investments. (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 March 31, 2023 Reinforcement Performance Consolidated Total (In millions) Americas $ 280 $ 100 $ 380 Asia Pacific 245 123 368 Europe, Middle East and Africa 147 103 250 Segment revenues from external customers 672 326 998 Unallocated and other 35 Net sales and other operating revenues $ 1,033 Three Months Ended March 31, 2022 Reinforcement Performance Purification Consolidated Total (In millions) Americas $ 256 $ 110 $ 16 $ 382 Asia Pacific 258 138 6 402 Europe, Middle East and Africa 140 115 14 269 Segment revenues from external customers 654 363 36 1,053 Unallocated and other 39 Net sales and other operating revenues $ 1,092 Six Months Ended March 31, 2023 Reinforcement Performance Purification Consolidated Total (In millions) Americas $ 521 $ 189 $ — $ 710 Asia Pacific 518 249 — 767 Europe, Middle East and Africa 276 174 — 450 Segment revenues from external customers 1,315 612 — 1,927 Unallocated and other 71 Net sales and other operating revenues $ 1,998 Six Months Ended March 31, 2022 Reinforcement Performance Purification Consolidated Total (In millions) Americas $ 465 $ 200 $ 43 $ 708 Asia Pacific 508 275 14 797 Europe, Middle East and Africa 244 194 40 478 Segment revenues from external customers 1,217 669 97 1,983 Unallocated and other 77 Net sales and other operating revenues $ 2,060

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	6 Months Ended
	Mar. 31, 2023
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements In August 2022, the U.S. government enacted the Inflation Reduction Act ("IRA") which, among other things, provides for a 1 % excise tax on stock repurchases. The IRA was effective January 1, 2023. The Company’s application of the statute did not have a material effect on its Consolidated Financial Statements, or its share repurchase program. In November 2022, the FASB issued a new standard on the disclosure of supplier financing programs. The new standard requires qualitative and quantitative disclosure as to the nature and potential magnitude of such programs in addition to program activity and changes for the periods presented. The standard is effective for fiscal years beginning after December 15, 2022 and early adoption is permitted. The Company is currently evaluating the timing of adoption and the impact of the adoption of this standard on its Consolidated Financial Statements.

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	6 Months Ended
	Mar. 31, 2023
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Changes in Balances	The carrying amount of goodwill attributable to each reportable segment and the changes in those balances during the six months ended March 31, 2023 are as follows: Reinforcement Performance Total (In millions) Balance at September 30, 2022 $ 46 $ 83 $ 129 Foreign currency impact 4 3 7 Balance at March 31, 2023 $ 50 $ 86 $ 136
Schedule of Intangible Assets	The following table provides information regarding the Company’s intangible assets: March 31, 2023 September 30, 2022 Gross Accumulated Net Gross Accumulated Net (In millions) Intangible assets with finite lives Developed technologies $ 34 $ ( 9 ) 25 $ 34 $ ( 8 ) $ 26 Trademarks 2 ( 1 ) 1 2 ( 1 ) 1 Customer relationships 64 ( 27 ) 37 59 ( 23 ) 36 Total intangible assets $ 100 $ ( 37 ) $ 63 $ 95 $ ( 32 ) $ 63

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) ("AOCI") (Tables)	6 Months Ended
	Mar. 31, 2023
Equity [Abstract]
Changes in Each Component of AOCI, Net of Tax	Changes in each component of AOCI, net of tax, were as follows: Currency Pension and Other Total (In millions) Balance at September 30, 2022, attributable to Cabot Corporation $ ( 429 ) $ ( 10 ) $ ( 439 ) Other comprehensive income (loss) before reclassifications 88 — 88 Amounts reclassified from AOCI ( 1 ) — ( 1 ) Less: Other comprehensive income (loss) attributable to 6 — 6 Balance at December 31, 2022, attributable to Cabot Corporation ( 348 ) ( 10 ) ( 358 ) Other comprehensive income (loss) before reclassifications 49 — 49 Amounts reclassified from AOCI ( 1 ) ( 1 ) ( 2 ) Less: Other comprehensive income (loss) attributable to 3 — 3 Balance at March 31, 2023, attributable to Cabot Corporation $ ( 303 ) $ ( 11 ) $ ( 314 )
Amounts Reclassified Out of AOCI	The amounts reclassified out of AOCI and into the Consolidated Statements of Operations in each of the three and six months ended March 31, 2023 and 2022 were are follows: Affected Line Item in the Consolidated Three Months Ended March 31 Six Months Ended March 31 Statements of Operations 2023 2022 2023 2022 (In millions) Derivatives: net investment hedges (Gains) losses reclassified to interest expense Interest expense $ ( 2 ) $ ( 2 ) $ ( 3 ) $ ( 3 ) (Gains) losses excluded from effectiveness testing and amortized to interest expense Interest expense 1 1 1 1 Release of currency translation adjustment Loss on sale of business and asset impairment charge — 33 — 33 Pension and other postretirement Release of actuarial losses and prior service cost (credit) Loss on sale of business and asset impairment charge — 1 — 1 Amortization of actuarial losses and prior service cost (credit) Other income (expense) ( 1 ) — ( 1 ) — Total before tax $ ( 2 ) $ 33 $ ( 3 ) $ 32

Income Tax (Tables)

Income Tax (Tables)	6 Months Ended
	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Effective Tax Rate	Effective Tax Rate Three Months Ended March 31 Six Months Ended March 31 2023 2022 2023 2022 (Dollars in millions) (Provision) benefit for income taxes $ ( 29 ) $ ( 36 ) $ ( 49 ) $ ( 24 ) Effective tax rate 26 % 24 % 25 % 44 %

Earnings Per Share (Tables)

Earnings Per Share (Tables)	6 Months Ended
	Mar. 31, 2023
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 March 31 Six Months Ended March 31 2023 2022 2023 2022 (In millions, except per share amounts) Basic EPS: Net income (loss) attributable to Cabot $ 75 $ 107 $ 129 $ 18 Less: Dividends and dividend equivalents 1 1 1 1 Less: Undistributed earnings allocated to (1) 1 1 2 — Earnings (loss) allocated to common $ 73 $ 105 $ 126 $ 17 Weighted average common shares and 57.6 57.5 57.6 57.4 Less: Participating securities (1) 1.3 0.9 1.3 0.9 Adjusted weighted average common 56.3 56.6 56.3 56.5 Earnings (loss) per common share - basic: $ 1.31 $ 1.86 $ 2.24 $ 0.30 Diluted EPS: Earnings (loss) allocated to common $ 73 $ 105 $ 126 $ 17 Plus: Earnings allocated to 2 2 3 1 Less: Adjusted earnings allocated to (2) 2 2 3 1 Earnings (loss) allocated to common $ 73 $ 105 $ 126 $ 17 Adjusted weighted average common 56.3 56.6 56.3 56.5 Effect of dilutive securities: Common shares issuable (3) 0.5 0.5 0.4 0.4 Adjusted weighted average common 56.8 57.1 56.7 56.9 Earnings (loss) per common share - diluted: $ 1.29 $ 1.84 $ 2.23 $ 0.30 (1) Participating securities consist of shares underlying unvested time-based restricted stock units (the "TSUs"), earned and unvested performance-based restricted stock units (the "PSUs", and referred to in this note collectively with the TSUs as the "RSUs"), stock units accounted for under the Supplemental 401(k) Plan portion of the Company’s Deferred Compensation and Supplemental Retirement Plan, and stock units and phantom stock units accounted for under the Company’s Non-Employee Directors’ Deferral Plan. The holders of RSUs are entitled to receive dividend equivalents, payable in cash, to the extent dividends are paid on the outstanding shares of Common Stock, and equal in value to the dividends that would have been paid in respect of the Common Stock underlying the RSU. The accounts of holders of stock units and phantom stock units are credited with dividend equivalents, which are payable, in stock or cash, as the case may be, with the distribution of account balances.
Calculation of Undistributed Earnings	The calculation of undistributed earnings is as follows: Three Months Ended March 31 Six Months Ended March 31 2023 2022 2023 2022 (In millions) Calculation of undistributed earnings (loss): Net income (loss) attributable to Cabot Corporation $ 75 $ 107 $ 129 $ 18 Less: Dividends declared on common stock 21 21 42 42 Less: Dividends declared on participating 1 1 1 1 Undistributed earnings (loss) $ 53 $ 85 $ 86 $ ( 25 ) Allocation of undistributed earnings (loss): Undistributed earnings (loss) allocated to $ 52 $ 84 $ 84 $ ( 25 ) Undistributed earnings allocated to 1 1 2 — Undistributed earnings (loss) $ 53 $ 85 $ 86 $ ( 25 ) (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 assumed exercise of stock options issued under Cabot’s equity incentive plans. For the three and six months ended March 31, 2023, 156,550 and 121,283 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. For the three and six months ended March 31, 2022, 242,031 and 356,476 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.

Financial Information by Segm_2

Financial Information by Segment (Tables)	6 Months Ended
	Mar. 31, 2023
Segment Reporting [Abstract]
Financial Information by Reportable Segment	Financial information by reportable segment is as follows: Reinforcement Performance Purification Segment Unallocated (1) Consolidated (In millions) Three Months Ended March 31, 2023 Revenues from external customers (3) $ 672 $ 326 $ — $ 998 $ 35 $ 1,033 Income (loss) before income taxes (4) $ 122 $ 28 $ — $ 150 $ ( 40 ) $ 110 Three Months Ended March 31, 2022 Revenues from external customers (2)(3) $ 654 $ 363 $ 36 $ 1,053 $ 39 $ 1,092 Income (loss) before income taxes (4) $ 101 $ 70 $ — $ 171 $ ( 24 ) $ 147 Six Months Ended March 31, 2023 Revenues from external customers (3) $ 1,315 $ 612 $ — $ 1,927 $ 71 $ 1,998 Income (loss) before income taxes (4) $ 216 $ 57 $ — $ 273 $ ( 79 ) $ 194 Six Months Ended March 31, 2022 Revenues from external customers (2)(3) $ 1,217 $ 669 $ 97 $ 1,983 $ 77 $ 2,060 Income (loss) before income taxes (4) $ 186 $ 122 $ — $ 308 $ ( 254 ) $ 54 (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) Beginning in the fiscal year 2023, the Company began allocating energy center by-product revenue within the applicable segment’s Revenue from external customers. The Company recast prior period financial information to conform to the new presentation. The allocation of such revenue resulted in an increase of $ 27 million in the Reinforcement Materials segment and $ 3 million in the Performance Chemicals segment, respectively, with an offsetting decrease in Unallocated and Other revenue for the three months ended March 31, 2022. The allocation of such revenue resulted in an increase of $ 49 million in the Reinforcement Materials segment and $ 7 million in the Performance Chemicals segment, respectively, with an offsetting decrease in Unallocated and Other revenue for the six months ended March 31, 2022. There was no impact to the Consolidated Total Revenues from external customers. (3) 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, discounting charges for certain Notes receivable, and other by-product revenue. Details are provided in the table below: Three Months Ended March 31 Six Months Ended March 31 2023 2022 2023 2022 (In millions) Shipping and handling fees $ 36 $ 41 $ 69 $ 80 Other ( 1 ) ( 2 ) 2 ( 3 ) Total $ 35 $ 39 $ 71 $ 77 (4) 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 March 31 Six Months Ended March 31 2023 2022 2023 2022 (In millions) Interest expense $ ( 23 ) $ ( 11 ) $ ( 45 ) $ ( 23 ) Certain items (a) Gain on bargain purchase of a business (Note C) — 24 — 24 Gain on sale of land — — 1 — Loss on sale of business and asset impairment charge (Note D) — ( 7 ) ( 3 ) ( 204 ) Legal and environmental matters and reserves ( 1 ) ( 7 ) ( 2 ) ( 8 ) Acquisition and integration-related charges — ( 2 ) ( 1 ) ( 3 ) Divestiture related charges — ( 1 ) — ( 5 ) Global restructuring activities — — — ( 2 ) Other ( 1 ) — ( 1 ) 1 Total certain items, pre-tax ( 2 ) 7 ( 6 ) ( 197 ) Unallocated corporate costs (b) ( 16 ) ( 16 ) ( 31 ) ( 30 ) General unallocated income (expense) (c) 2 ( 1 ) 6 — Less: Equity in earnings of affiliated companies, net (d) 1 3 3 4 Total $ ( 40 ) $ ( 24 ) $ ( 79 ) $ ( 254 ) (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 and unrealized holding gains (losses) for investments. (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.
Revenues from External Customers by Geographic Region	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 March 31, 2023 Reinforcement Performance Consolidated Total (In millions) Americas $ 280 $ 100 $ 380 Asia Pacific 245 123 368 Europe, Middle East and Africa 147 103 250 Segment revenues from external customers 672 326 998 Unallocated and other 35 Net sales and other operating revenues $ 1,033 Three Months Ended March 31, 2022 Reinforcement Performance Purification Consolidated Total (In millions) Americas $ 256 $ 110 $ 16 $ 382 Asia Pacific 258 138 6 402 Europe, Middle East and Africa 140 115 14 269 Segment revenues from external customers 654 363 36 1,053 Unallocated and other 39 Net sales and other operating revenues $ 1,092 Six Months Ended March 31, 2023 Reinforcement Performance Purification Consolidated Total (In millions) Americas $ 521 $ 189 $ — $ 710 Asia Pacific 518 249 — 767 Europe, Middle East and Africa 276 174 — 450 Segment revenues from external customers 1,315 612 — 1,927 Unallocated and other 71 Net sales and other operating revenues $ 1,998 Six Months Ended March 31, 2022 Reinforcement Performance Purification Consolidated Total (In millions) Americas $ 465 $ 200 $ 43 $ 708 Asia Pacific 508 275 14 797 Europe, Middle East and Africa 244 194 40 478 Segment revenues from external customers 1,217 669 97 1,983 Unallocated and other 77 Net sales and other operating revenues $ 2,060

Significant Accounting Polici_3

Significant Accounting Policies - Additional Information (Detail)	1 Months Ended
	Aug. 31, 2022
Accounting Policies [Abstract]
Excise tax on stock repurchases	1%

Acquisition - Additional Inform

Acquisition - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended	6 Months Ended
	Feb. 28, 2022	Mar. 31, 2022	Mar. 31, 2022
Business Acquisition [Line Items]
Businesses acquisition, net of cash acquired			$ (5)
Gain on bargain purchase of a business			$ 24
Tokai Carbon Group Tianjin Co
Business Acquisition [Line Items]
Business acquisition, purchase price	$ 9
Business acquisition, cash consideration	14
Businesses acquisition, net of cash acquired	$ 5
Tokai Carbon Group Tianjin Co | Accounts Payable and Accrued Liabilities [Member]
Business Acquisition [Line Items]
Gain on bargain purchase of a business		$ 24
Tokai Carbon Group Tianjin Co | Tokai Carbon's Registered Capital [Member]
Business Acquisition [Line Items]
Business acquisition, ownership percentage	100%

Divestitures - Additional Infor

Divestitures - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended			6 Months Ended		12 Months Ended
	Mar. 31, 2022	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2023	Mar. 31, 2022	Sep. 30, 2022
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from sale of business					$ 6	$ 79
Impairment charge			$ 7		$ 3	$ 204
Purification Solutions [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Pre-tax loss on sale							$ 10
Impairment charge				$ 197
Additional pre-tax loss on sale of business		$ 3
Purification Solutions [Member] | One Equity Partners [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from sale of business	$ 85
Proceeds from divestiture of cash transferred	$ 7

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Schedule of Changes in Balances (Detail) $ in Millions	6 Months Ended
	Mar. 31, 2023 USD ($)
Goodwill And Intangible Assets [Line Items]
Beginning balance	$ 129
Foreign currency impact	7
Ending balance	136
Reinforcement Materials [Member]
Goodwill And Intangible Assets [Line Items]
Beginning balance	46
Foreign currency impact	4
Ending balance	50
Performance Chemicals [Member]
Goodwill And Intangible Assets [Line Items]
Beginning balance	83
Foreign currency impact	3
Ending balance	$ 86

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Millions	Mar. 31, 2023	Sep. 30, 2022
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value, finite lives	$ 100	$ 95
Accumulated Amortization	(37)	(32)
Net Intangible Assets, finite lives	63	63
Developed Technologies [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value, finite lives	34	34
Accumulated Amortization	(9)	(8)
Net Intangible Assets, finite lives	25	26
Trademarks [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value, finite lives	2	2
Accumulated Amortization	(1)	(1)
Net Intangible Assets, finite lives	1	1
Customer Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value, finite lives	64	59
Accumulated Amortization	(27)	(23)
Net Intangible Assets, finite lives	$ 37	$ 36

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Goodwill And Intangible Assets [Line Items]
Amortization expense estimated for year one	$ 6		$ 6
Amortization expense estimated for year two	6		6
Amortization expense estimated for year three	6		6
Amortization expense estimated for year four	6		6
Amortization expense estimated for year five	6		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	$ 1	$ 3	$ 3
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 Comprehensi_3

Accumulated Other Comprehensive Income (Loss) ("AOCI") - Changes in Each Component of AOCI, Net of Tax (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	$ 1,159	$ 1,032
Ending Balance	1,232	1,159
Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(348)	(429)
Other comprehensive income (loss) before reclassifications	49	88
Amounts reclassified from AOCI	(1)	(1)
Less: Other comprehensive income (loss) attributable to noncontrolling interests	3	6
Ending Balance	(303)	(348)
Pension and Other Postretirement Benefit Liability Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(10)	(10)
Amounts reclassified from AOCI	(1)
Ending Balance	(11)	(10)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(358)	(439)
Other comprehensive income (loss) before reclassifications	49	88
Amounts reclassified from AOCI	(2)	(1)
Less: Other comprehensive income (loss) attributable to noncontrolling interests	3	6
Ending Balance	$ (314)	$ (358)

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Income (Loss) ("AOCI") - Amounts Reclassified Out of AOCI (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	$ (2)	$ 33	$ (3)	$ 32
(Gains) Losses Reclassified to Interest Expense [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	(2)	(2)	(3)	(3)
(Gains) Losses Excluded from Effectiveness Testing and Amortized to Interest Expense [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	1	1	1	1
Release of Currency Translation Adjustment [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax		33		33
Release of Actuarial Losses and Prior Service Cost (Credit) [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)		$ (1)

Contingencies - Additional Info

Contingencies - Additional Information (Detail) - USD ($) $ in Millions	Mar. 31, 2023	Sep. 30, 2022
Respirator Liabilities [Member]
Loss Contingencies [Line Items]
Respirator reserve	$ 38	$ 39

Insurance Recoveries - Addition

Insurance Recoveries - Additional Information (Detail) - Pepinster, Belgium [Member] - Flood [Member] - USD ($)	3 Months Ended			6 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Sep. 30, 2022
Business Interruption Loss [Line Items]
Flood-related expenses	$ 0		$ 1,000,000	$ 0	$ 6,000,000
Insurance proceeds recorded	8,000,000			14,000,000
Insurance gain proceeds	4,000,000			9,000,000
Insurance loss proceeds	0			1,000,000
Cash provided by investing activities		$ 6,000,000
Insurance settlements receivable	$ 8,000,000			$ 8,000,000		$ 4,000,000

Income Tax - Effective Tax Rate

Income Tax - Effective Tax Rate (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Income Tax Disclosure [Abstract]
(Provision) benefit for income taxes	$ (29)	$ (36)	$ (49)	$ (24)
Effective tax rate	26%	24%	25%	44%

Income Tax - Additional Informa

Income Tax - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Income Taxes [Line Items]
Net discrete tax (benefits) expense related to tax settlements		$ 1		$ (36)
Income tax benefit from tax loss related to divestiture	$ 2
Tax expense related to withholding tax accruals on historic earnings due to changes in indefinite reinvestment assertion on certain entities			$ 1
Uncertain tax positions from expirations of statute of limitations	$ 1	$ 1	$ 1	$ 2
United States Internal Revenue Service (IRS) [Member] | Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2019
United States Internal Revenue Service (IRS) [Member] | Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2021
State Tax Authorities [Member] | Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2009
State Tax Authorities [Member] | Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2021
Foreign Jurisdictions [Member] | Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2005
Foreign Jurisdictions [Member] | Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination			2022
Purification Solutions [Member]
Income Taxes [Line Items]
Net discrete tax (benefits) expense related to tax settlements			$ (36)

Earnings Per Share - Components

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		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Basic EPS:
Net income (loss) attributable to Cabot Corporation	$ 75	$ 107	$ 129	$ 18
Less: Dividends and dividend equivalents to participating securities	1	1	1	1
Less: Undistributed earnings allocated to participating securities	1	1	2
Earnings (loss) allocated to common shareholders (numerator)	$ 73	$ 105	$ 126	$ 17
Weighted average common shares and participating securities outstanding	57.6	57.5	57.6	57.4
Less: Participating securities	1.3	0.9	1.3	0.9
Adjusted weighted average common shares (denominator)	56.3	56.6	56.3	56.5
Earnings (loss) per common share - basic:	$ 1.31	$ 1.86	$ 2.24	$ 0.30
Diluted EPS:
Earnings (loss) allocated to common shareholders	$ 73	$ 105	$ 126	$ 17
Plus: Earnings allocated to participating securities	2	2	3	1
Less: Adjusted earnings allocated to participating securities	2	2	3	1
Earnings (loss) allocated to common shareholders (numerator)	$ 73	$ 105	$ 126	$ 17
Adjusted weighted average common shares outstanding	56.3	56.6	56.3	56.5
Common shares issuable	0.5	0.5	0.4	0.4
Adjusted weighted average common shares (denominator)	56.8	57.1	56.7	56.9
Earnings (loss) per common share - diluted:	$ 1.29	$ 1.84	$ 2.23	$ 0.30

Earnings Per Share - Calculatio

Earnings Per Share - Calculation of Undistributed Earnings (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Earnings Per Share [Abstract]
Net income (loss) attributable to Cabot Corporation	$ 75	$ 107	$ 129	$ 18
Less: Dividends declared on common stock	21	21	42	42
Less: Dividends declared on participating securities	1	1	1	1
Undistributed earnings (loss)	53	85	86	(25)
Undistributed earnings (loss) allocated to common shareholders	52	84	84	$ (25)
Undistributed earnings allocated to participating shareholders	$ 1	$ 1	$ 2

Earnings Per Share - Componen_2

Earnings Per Share - Components of Basic and Diluted Earnings (Loss) Per Common Share (EPS) (Parenthetical) (Detail) - shares	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Earnings Per Share [Abstract]
Antidilutive securities excluded from computation of earnings per share	156,550	242,031	121,283	356,476

Financial Instruments and Fai_2

Financial Instruments and Fair Value Measurements - Additional Information (Detail) - USD ($)	6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Sep. 30, 2022
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	1,090,000,000		$ 1,060,000,000
Fixed Rate Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value of long-term debt	1,080,000,000		1,080,000,000
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	9,000,000		8,000,000
Significant Observable Inputs (Level 2) [Member] | Foreign Currency Risks [Member] | Prepaid Expenses and Other Current Assets Accounts Payable and Accrued Liabilities and Other Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets (liabilities) net, at fair Value	$ 11,000,000
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) net, at fair Value			$ 28,000,000

Financial Information by Segm_3

Financial Information by Segment - Additional Information (Detail)	6 Months Ended
	Mar. 31, 2023 Segment
Segment Reporting Information [Line Items]
Number of business reportable segments	2
Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Number of business reportable segments	1

Financial Information by Segm_4

Financial Information by Segment - Financial Information by Reportable Segment (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information [Line Items]
Revenues from external customers	$ 1,033	$ 1,092	$ 1,998	$ 2,060
Income (loss) before income taxes	110	147	194	54
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	998	1,053	1,927	1,983
Income (loss) before income taxes	150	171	273	308
Unallocated and Other [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	35	39	71	77
Income (loss) before income taxes	(40)	(24)	(79)	(254)
Reinforcement Materials [Member]
Segment Reporting Information [Line Items]
Revenues from external customers		49	27
Reinforcement Materials [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	672	654	1,315	1,217
Income (loss) before income taxes	122	101	216	186
Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Revenues from external customers		7	3
Performance Chemicals [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	326	363	612	669
Income (loss) before income taxes	$ 28	70	$ 57	122
Purification Solutions [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers		$ 36		$ 97

Financial Information by Segm_5

Financial Information by Segment - Financial Information by Reportable Segment (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information [Line Items]
Revenues from external customers	$ 1,033	$ 1,092	$ 1,998	$ 2,060
Reinforcement Materials [Member]
Segment Reporting Information [Line Items]
Revenues from external customers		49	27
Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Revenues from external customers		$ 7	$ 3

Financial Information by Segm_6

Financial Information by Segment - Revenues From External Customers That are Categorized as Unallocated and Other Reflects Royalties, External Shipping and Handling Fees, The Impact of Unearned Revenue, Discounting Charges For Certain Notes Receivable, and Other By-product Revenue (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information [Line Items]
Revenues from external customers	$ 1,033	$ 1,092	$ 1,998	$ 2,060
Unallocated and Other [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	35	39	71	77
Unallocated and Other [Member] | Shipping and Handling Costs [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	36	41	69	80
Unallocated and Other [Member] | Other [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	$ (1)	$ (2)	$ 2	$ (3)

Financial Information by Segm_7

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		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information [Line Items]
Interest expense	$ (23)	$ (11)	$ (45)	$ (23)
Gain on bargain purchase of a business		24		24
Gain on sale of land			1
Loss on sale of business and asset impairment charge (Note D)		7	3	204
Unallocated and Other [Member]
Segment Reporting Information [Line Items]
Interest expense	(23)	(11)	(45)	(23)
Unallocated corporate costs	(16)	(16)	(31)	(30)
General unallocated income (expense)	2	(1)	6
Less: Equity in earnings of affiliated companies, net of tax	1	3	3	4
Income from continuing operations before income taxes and equity in earnings of affiliated companies	(40)	(24)	(79)	(254)
Certain Items [Member]
Segment Reporting Information [Line Items]
Gain on bargain purchase of a business		24		24
Gain on sale of land			1
Loss on sale of business and asset impairment charge (Note D)		(7)	(3)	(204)
Legal and environmental matters and reserves	(1)	(7)	(2)	(8)
Acquisition and integration-related charges		(2)	(1)	(3)
Divestiture related charges		(1)		(5)
Global restructuring activities				(2)
Other	(1)		(1)	1
Total certain items, pre-tax	$ (2)	$ 7	$ (6)	$ (197)

Financial Information by Segm_8

Financial Information by Segment - Revenue from External Customers by Geographic Region (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information [Line Items]
Net sales and other operating revenues	$ 1,033	$ 1,092	$ 1,998	$ 2,060
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	998	1,053	1,927	1,983
Unallocated and Other [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	35	39	71	77
Americas [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	380	382	710	708
Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	368	402	767	797
Europe, Middle East and Africa [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	250	269	450	478
Reinforcement Materials [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues		49	27
Reinforcement Materials [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	672	654	1,315	1,217
Reinforcement Materials [Member] | Americas [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	280	256	521	465
Reinforcement Materials [Member] | Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	245	258	518	508
Reinforcement Materials [Member] | Europe, Middle East and Africa [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	147	140	276	244
Performance Chemicals [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues		7	3
Performance Chemicals [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	326	363	612	669
Performance Chemicals [Member] | Americas [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	100	110	189	200
Performance Chemicals [Member] | Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	123	138	249	275
Performance Chemicals [Member] | Europe, Middle East and Africa [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues	$ 103	115	$ 174	194
Purification Solutions [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues		36		97
Purification Solutions [Member] | Americas [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues		16		43
Purification Solutions [Member] | Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues		6		14
Purification Solutions [Member] | Europe, Middle East and Africa [Member]
Segment Reporting Information [Line Items]
Net sales and other operating revenues		$ 14		$ 40