CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2022	Jul. 31, 2021
Statement of Comprehensive Income [Abstract]
Net gain on derivative instruments, tax (benefit)	$ (4)	$ (2)	$ (12)	$ (4)
Change in net unrealized gain on available-for-sale securities, tax expense (benefit)	0	0	0	0
Change in defined benefit pension items, tax effect	0	0	0	0
Net change in cumulative foreign currency translation loss, tax expense (benefit)	$ 1	$ 1	$ 1	$ (1)