Net Income Per Share - Computation of Net Income Per Share Amounts (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended				6 Months Ended
	Jul. 31, 2022	Apr. 30, 2022	Jul. 31, 2021	Apr. 30, 2021	Jul. 31, 2022	Jul. 31, 2021
Numerator:
Net income	$ 186	$ 146	$ 115	$ 156	$ 332	$ 271
Denominator:
Denominator for basic net income per share—weighted average shares (in shares)	217		220		217	220
Effect of dilutive securities (in shares)	1		2		1	2
Denominator for dilutive net income per share (in shares)	218		222		218	222
Basic net income per share (in dollars per share)	$ 0.86		$ 0.52		$ 1.53	$ 1.23
Diluted net income per share (in dollars per share)	$ 0.85		$ 0.52		$ 1.52	$ 1.22