Investments - Schedule of Short-Term and Long-Term Marketable Securities (Details) - USD ($) $ in Millions	Oct. 31, 2025	Jan. 31, 2025
Investments, Debt and Equity Securities [Abstract]
Due within 1 year	$ 462	$ 2,081
Due in 1 year through 5 years	1,882	3,098
Due in 5 years through 10 years	1	5
Fair value of marketable securities	$ 2,345	$ 5,184