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				6 Months Ended
	Jul. 31, 2025	Apr. 30, 2025	Jul. 31, 2024	Apr. 30, 2024	Jul. 31, 2025	Jul. 31, 2024
Numerator:
Net income	$ 1,887	$ 1,541	$ 1,429	$ 1,533	$ 3,428	$ 2,962
Denominator:
Weighted-average shares outstanding for basic net income per share (in shares)	956		964		958	967
Employee stock awards (in shares)	6		9		8	12
Weighted-average shares outstanding for diluted net income per share (in shares)	962		973		966	979