Derivative Instruments | Derivatives not Designated as Hedges (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Derivative [Line Items]
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	$ (8.3)	$ (27.1)	$ (32.7)
Cost of Sales [Member]
Derivative [Line Items]
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	(3.0)	17.7	(24.3)
Nonoperating Income (Expense) [Member]
Derivative [Line Items]
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	$ (5.3)	$ (44.8)	$ (8.4)