Stockholders' Equity - Share-based Compensation, Stock Options, Activity (Details) $ / shares in Units, shares in Millions, $ in Millions	9 Months Ended
	Oct. 31, 2021 USD ($) $ / shares shares
Outstanding Stock Options
Beginning balance (in shares) | shares	23
Options granted under all plans (in shares) | shares	8
Exercised (in shares) | shares	(6)
Plan shares expired or canceled (in shares) | shares	(2)
Ending balance (in shares) | shares	23
Outstanding Stock Options, Vested or expected to vest (in shares) | shares	21
Outstanding Stock Options, Exercisable (in shares) | shares	9
Options Outstanding Weighted-Average Exercise Price
Beginning balance (in dollars per share) | $ / shares	$ 120.61
Options granted under all plans (in dollars per share) | $ / shares	198.66
Exercised (in dollars per share) | $ / shares	89.80
Plan shares expired or canceled (in dollars per share) | $ / shares	161.30
Ending balance (in dollars per share) | $ / shares	152.07
Weighted-Average Exercise Price, Vested or expected to vest (in dollars per share) | $ / shares	149.21
Weighted-Average Exercise Price, Exercisable (in dollars per share) | $ / shares	$ 109.41
Aggregate Intrinsic Value
Balance | $	$ 3,329
Vested or expected to vest | $	3,147
Exercisable | $	$ 1,753