Hedging Activities, Derivative Instruments and Credit Risk - Derivative Instruments not Designated as Accounting Hedges (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments at Fair Value, Net [Abstract]
Total foreign currency transaction gains (losses), net	$ (20.9)	$ (8.1)	$ 1.9
Foreign currency forward contracts gains (losses)
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments at Fair Value, Net [Abstract]
Total foreign currency transaction gains (losses), net	$ 15.0	$ (4.9)	$ 5.2