Other Operating Income, Net and Other Non-Operating Income (Expense), Net - Schedule of Other Non-Operating (Expense) Income, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Component of Operating Income [Abstract]
(Losses) gains on foreign currency contracts, net	$ (23)	$ 63	$ 9
Amortization of excluded components of certain net investment hedges	7	7	2
Pension and other postretirement plans non-service income, net	9	5	1
Total other non-operating (expense) income, net	$ (7)	$ 75	$ 12