Derivative Instruments | Derivatives not Designated as Hedges (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 30, 2019	Apr. 30, 2018
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	$ 0.6	$ (0.7)
Cost of Sales [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	0.9	6.6
Nonoperating Income (Expense) [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	$ (0.3)	$ (7.3)