Gains and Losses on Forward Currency Contracts Outstanding and Total Net Foreign Currency Gains and Losses (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011
Schedule of Foreign Currency Balance [Line Items]
Foreign currency forward contracts gains	$ 738		$ 2,747		$ 684		$ 742
Total net foreign currency gains	$ (94)	[1]	$ (25)	[1]	$ (1,245)	[1]	$ (2,614)	[1]

[1] See Note 13 "Supplemental Information"