Nonconsolidated Partially-Owned Affiliates - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2024
Schedule of Equity Method Investments [Line Items]
Investments in partially-owned affiliates	$ 303		$ 338
KEIPER | Supply Commitment
Schedule of Equity Method Investments [Line Items]
Reduction in cost of revenue	25	$ 14
Reduction in equity income	34	$ 17
Asia
Schedule of Equity Method Investments [Line Items]
Non-cash impairment charges	3
EMEA
Schedule of Equity Method Investments [Line Items]
Non-cash impairment charges	$ 3