Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash Flows from Operating Activities:
Net income (loss)	$ 140	$ 250
Adjustments to reconcile net income (loss) to cash provided by operating activities:
Depreciation and amortization	111	117
Loss on sale of business and asset impairment charge	206
Gain on bargain purchase of a business	(24)
Gain on sale of land	(17)
Deferred tax provision (benefit)	(39)	4
Employee benefit plan settlement		7
Equity in earnings of affiliated companies	(7)	(3)
Non-cash compensation	17	16
Other non-cash (income) expense	15	10
Cash dividends received from equity affiliates	1	2
Changes in assets and liabilities:
Accounts and notes receivable	(286)	(198)
Inventories	(231)	(125)
Prepaid expenses and other assets	(35)	(15)
Accounts payable and accrued liabilities	127	97
Income taxes payable	18	12
Other liabilities	(1)	(17)
Cash provided (used) by operating activities	(5)	157
Cash Flows from Investing Activities:
Additions to property, plant and equipment	(121)	(115)
Proceeds from sale of business	79
Cash paid for acquisition of business, net of cash acquired of $5 and $-	(9)
Proceeds from sale of land	18
Other	2	5
Cash provided (used) by investing activities	(31)	(110)
Cash Flows from Financing Activities:
Proceeds from short-term borrowings	26
Proceeds from issuance (repayments) of commercial paper, net	193	46
Proceeds from long-term debt, net of issuance costs	394	150
Repayments of long-term debt	(357)	(167)
Purchases of common stock	(48)	(2)
Proceeds from sales of common stock	6	5
Cash dividends paid to noncontrolling interests	(22)	(20)
Cash dividends paid to common stockholders	(63)	(60)
Cash provided (used) by financing activities	129	(48)
Effects of exchange rate changes on cash	(49)	23
Increase (decrease) in cash, cash equivalents and restricted cash	44	22
Cash, cash equivalents and restricted cash at beginning of period	170	151
Cash, cash equivalents and restricted cash at end of period	214	173
Cash and cash equivalents	208	$ 173
Restricted cash classified within Prepaid expenses and other current assets	$ 6
Restricted Cash and Cash Equivalents, Current, Statement of Financial Position [Extensible Enumeration]	http://www.cabotcorp.com/#PrepaidExpensesAndOtherCurrentAssets	http://www.cabotcorp.com/#PrepaidExpensesAndOtherCurrentAssets
Cash, cash equivalents and restricted cash	$ 214	$ 173