Income Taxes - Income Tax Expense by Fiscal Year (Detail) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Current:
U.S. federal	$ 2,630	$ 2,166	$ 1,943
State and local	293	104	69
Non-U.S.	1,324	1,245	869
Total current taxes	4,247	3,515	2,881
Deferred:
U.S. federal	(339)	(231)	(57)
State and local	(1)	(77)	(28)
Non-U.S.	(143)	(28)	956
Total deferred taxes	(483)	(336)	871
Total income tax provision	$ 3,764	$ 3,179	$ 3,752

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