Leases and Other Commitments - Components of Lease Expense and Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2022	Jan. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Operating lease cost	$ 1,080	$ 1,208
Finance lease cost:
Amortization of right-of-use assets	125	73
Interest on lease liabilities	5	15
Total finance lease cost	130	88
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash outflows for operating leases	873	905
Operating cash outflows for finance leases	5	14
Financing cash outflows for finance leases	74	48
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	$ 364	$ 979