Revenues - Contract Balances and Unearned Revenue (Details) $ in Millions	12 Months Ended
	Jan. 31, 2022 USD ($)	Jan. 31, 2021 USD ($)
Revenue from Contract with Customer [Abstract]
Customer contract assets	$ 587	$ 477
Unearned Revenue [Roll Forward]
Unearned revenue, beginning of period	12,607	10,662
Billings and other	29,011	23,096
Contribution from contract asset	110	28
Unearned revenue from business combinations	392	73
Unearned revenue, end of period	$ 15,628	12,607
Percent of revenue recognized	0.47
Revenue recognized over time
Unearned Revenue [Roll Forward]
Revenue recognized	$ (24,841)	(19,955)
Revenue recognized at a point in time
Unearned Revenue [Roll Forward]
Revenue recognized	$ (1,651)	$ (1,297)