CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 497.0	$ 1,208.2	$ 214.5
Other comprehensive income (loss), net of reclassifications:
Net gain (loss) on derivative instruments (net of tax effect of $(8.3), $5.0, and $(1.1))	48.3	(32.5)	(6.6)
Change in net unrealized gain on available-for-sale securities (net of tax effect of zero, $0.1, and $(0.4))	11.8	1.7	1.4
Change in defined benefit pension items (net of tax effect of $(0.7), $(0.3), and $1.6)	4.7	1.5	(6.5)
Net change in cumulative foreign currency translation (loss) gain (net of tax effect of $0.3, $(0.6), and $0.1)	(62.9)	63.7	(13.6)
Total other comprehensive income (loss)	1.9	34.4	(25.3)
Total comprehensive income	$ 498.9	$ 1,242.6	$ 189.2