Derivative Financial Instruments - Gain or Loss Recognized in Income (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Interest expense, net | Interest rate derivatives
Trading Activity, Gains and Losses, Net [Line Items]
Amount recognized as (income) expense	$ (0.8)	$ (5.0)	$ 0.0
Foreign currency forward contracts | Other expense (income), net
Trading Activity, Gains and Losses, Net [Line Items]
Amount recognized as (income) expense	$ 0.2	$ 0.0	$ (0.5)