Derivatives Not Designated as Hedging Instruments by Classification and Amount of Gains and Losses (Detail) (Not Designated As Hedging Instrument, USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) recognized in the statements of operations for derivatives not designated as hedging instruments	$ (13,372)	$ 20,695
Foreign Exchange Forward | Non-Operating Income Expense Classification
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) recognized in the statements of operations for derivatives not designated as hedging instruments	(13,775)	20,448
Foreign Exchange Forward | Cost of Sales Classification
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) recognized in the statements of operations for derivatives not designated as hedging instruments	$ 403	$ 247