Stockholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of the options exercised during the period	$ 1,200	$ 1,200	$ 800
Weighted-average remaining contractual life of vested and expected to vest options (in years)	5 years
Options vested (in shares)	9,000,000
Weighted average exercise price vested (in dollars per share)	$ 115.76
Remaining contractual term (in years)	3 years
Total intrinsic value of vested options	$ 1,709
Weighted-average fair value per share of grants (in dollars per share)	$ 0.001
Period for recognition (in years)	2 years
Fair value of shares vested in period	$ 3,200	$ 2,500
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares outstanding (in shares)	0	0
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of stock options (in years)	7 years
Weighted-average fair value per share of grants (in dollars per share)	$ 59.34	$ 41.24	$ 39.59
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Performance shares | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	0.00%
Performance shares | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	200.00%
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period for recognition (in years)	4 years