Taxes (Schedule of Income Tax Provision) (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Current:
U.S. federal	$ 3,313	$ 2,991	$ 2,794
U.S. state and local	649	742	587
International	1,553	1,127	1,205
Total current tax provision	5,515	4,860	4,586
Deferred:
U.S. federal	(671)	2,316	663
U.S. state and local	41	23	35
International	(129)	(341)	(369)
Total deferred tax expense (benefit)	(759)	1,998	329
Total provision for income taxes	$ 4,756	$ 6,858	$ 4,915