Derivative Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Notional amount of foreign currency derivative	$ 188.6	$ 238.7
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Notional amount of foreign currency derivative	116.8	160.7
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Notional amount of foreign currency derivative	$ 71.8	$ 78.0