Goodwill and Intangible Assets (Tables)

6 Months Ended

Mar. 31, 2024

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, 2024 are as follows:

	Reinforcement Materials		Performance Chemicals		Total
	(In millions)
Balance at September 30, 2023	$	51	$	83	$	134
Foreign currency impact		2		1		3
Balance at March 31, 2024	$	53	$	84	$	137

Schedule of Intangible Assets

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

	March 31, 2024							September 30, 2023
	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	$	34	$	(11	)	$	23	$	34	$	(10	)	$	24
Trademarks		2		(1	)		1		2		(1	)		1
Customer relationships		68		(33	)		35		65		(30	)		35
Total intangible assets	$	104	$	(45	)	$	59	$	101	$	(41	)	$	60