Derivative Instruments and Hedging Activities - Effect of Derivative Instruments on Consolidated Statements of Operations and Comprehensive Income (Detail) (Currency Forward Contracts [Member], Cash Flow Hedging Relationship [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) recognized in OCI on Derivatives	$ 20	$ 71	$ (75)	$ 75
SG&A [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) reclassified from Accumulated OCI to Income (Expense)	(16)	5	(12)	5
Other Income/(Expense) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) recognized in Income (Expense) on Derivatives	$ (40)	$ 24	$ 1	$ 25