Net Income Per Share - Reconciliation of Denominator Used in Calculation of Basic and Diluted Earnings Per Share (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended						9 Months Ended
	Oct. 31, 2025	Jul. 31, 2025	Apr. 30, 2025	Oct. 31, 2024	Jul. 31, 2024	Apr. 30, 2024	Oct. 31, 2025	Oct. 31, 2024
Numerator:
Net income	$ 2,086	$ 1,887	$ 1,541	$ 1,527	$ 1,429	$ 1,533	$ 5,514	$ 4,489
Denominator:
Weighted-average shares outstanding for basic net income per share (in shares)	948			956			955	963
Employee stock awards (in shares)	4			9			7	12
Weighted-average shares outstanding for diluted net income per share (in shares)	952			965			962	975