Hedging Activities and Fair Value Measurements, Derivative Instruments not Designated as Accounting Hedges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Derivative instruments not designated as accounting hedges [Abstract]
Total net foreign currency (losses) gains	$ (1.7)	$ (0.5)	$ (6.3)	$ 2.6
Foreign Currency Forwards [Member]
Derivative instruments not designated as accounting hedges [Abstract]
Total net foreign currency (losses) gains	$ (1.8)	$ 1.8	$ (6.7)	$ 14.0