Derivatives and Hedging Activities - Effect of Derivative Instruments on Condensed Consolidated Statements of Operations (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in Earnings on Derivatives	$ (1.7)	$ 5.5
Derivatives designated as hedging instruments | Cash Flow Hedge
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in Earnings on Derivatives	(0.6)	0.2
Derivatives designated as hedging instruments | Cash Flow Hedge | Foreign currency forward contracts
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in Earnings on Derivatives	(0.6)	0.1
Derivatives designated as hedging instruments | Cash Flow Hedge | Treasury locks
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in Earnings on Derivatives	0.0	0.1
Derivatives designated as hedging instruments | Fair Value Hedges | Interest rate swaps
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in Earnings on Derivatives	0.1	0.1
Derivatives not designated as hedging instruments | Foreign currency forward contracts
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in Earnings on Derivatives	$ (1.2)	$ 5.2