Derivatives and Hedging Instruments - Summary of Effects of Derivatives Not Designated as Hedging Instruments (Details) - Derivatives not designated as hedging instruments - Cash Flow Hedging - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Foreign currency exchange contracts | Other income (expense)
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivative	$ (833)	$ 3,330	$ 1,790	$ 10,706
Interest rate swap agreements | Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivative	0	39	110	83
Interest rate cap contracts | Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivative	$ 919	$ 0	$ 919	$ 0