Investments - Components of Gains and Losses on Strategic Investments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 31, 2025	Oct. 31, 2024	Oct. 31, 2025	Oct. 31, 2024
Investment Holdings [Line Items]
Unrealized gains (losses) recognized, net	$ 259	$ (216)	$ 183	$ (276)
Realized gains (losses) on sales of securities, net	4	(1)	23	59
Gains (losses) on strategic investments, net	263	(217)	206	(217)
Publicly traded equity securities
Investment Holdings [Line Items]
Unrealized gains (losses) recognized, net	0	8	(3)	(11)
Privately held equity securities
Investment Holdings [Line Items]
Unrealized gains (losses) recognized, net	428	18	488	167
Privately held equity and other investments
Investment Holdings [Line Items]
Impairments on privately held equity securities and other investments	$ (169)	$ (242)	$ (302)	$ (432)