Accumulated Other Comprehensive Income (Loss) ("AOCI")

6 Months Ended

Mar. 31, 2024

Stockholders' Equity Note [Abstract]

Accumulated Other Comprehensive Income (Loss) ("AOCI")

D. 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 Post-retirement Benefit Liability Adjustments			Total
	(In millions)
Balance at September 30, 2023, attributable to Cabot Corporation	$	(353	)	$	(9	)	$	(362	)
Other comprehensive income (loss) before reclassifications		62			—			62
Amounts reclassified from AOCI		(1	)		—			(1	)
Less: Other comprehensive income (loss) attributable to    noncontrolling interests		4			—			4
Balance at December 31, 2023, attributable to Cabot Corporation	$	(296	)	$	(9	)	$	(305	)
Other comprehensive income (loss) before reclassifications		(15	)		—			(15	)
Amounts reclassified from AOCI		—			(1	)		(1	)
Less: Other comprehensive income (loss) attributable to    noncontrolling interests		(4	)		—			(4	)
Balance at March 31, 2024, attributable to Cabot Corporation	$	(307	)	$	(10	)	$	(317	)

	Currency Translation Adjustment			Pension and Other Post-retirement Benefit Liability Adjustments			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    noncontrolling interests		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    noncontrolling interests		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, 2024 and 2023 are as follows:

	Affected Line Item in the Consolidated	Three Months Ended March 31						Six Months Ended March 31
	Statements of Operations	2024			2023			2024			2023
		(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
Pension and other postretirement
Amortization of actuarial losses and prior service cost (credit)	Other income (expense)		(1	)		(1	)		(1	)		(1	)
Total before tax		$	(2	)	$	(2	)	$	(3	)	$	(3	)