Derivative Instruments - Derivatives Designated as Hedging Instruments by Classification and Amount of Gains and Losses (Detail) - Designated As Hedging Instrument - Foreign Exchange Forward - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain recognized in OCI	$ 18,733	$ 37,926	$ 39,931
Cost of Sales Classification
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) reclassified from accumulated OCI to statements of operations	$ 16,627	$ 52,588	$ (883)