Derivative Instruments - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2013 USD ($)	Jun. 30, 2012 USD ($)	Jun. 30, 2013 USD ($)	Jun. 30, 2012 USD ($)	Jun. 30, 2013 EUR (€)	Dec. 31, 2012 USD ($)	Dec. 31, 2012 EUR (€)	Jun. 30, 2013 Accrued Liabilities USD ($)	Jun. 30, 2013 Other Noncurrent Liabilities USD ($)	Dec. 31, 2012 Prepaid Expenses and Other Current Assets USD ($)	Dec. 31, 2012 Other Long Lived Assets USD ($)
Derivatives Fair Value [Line Items]
Foreign currency forward contracts, notional amount	$ 15,600,000		$ 15,600,000		€ 12,000,000	$ 22,200,000	€ 16,800,000
Derivative liabilities								175,000	53,000
Derivative assets										30,000	21,000
Foreign currency forward contracts unrealized gain (loss)	182,000	(694,000)	(352,000)	(694,000)
Foreign currency forward contracts realized gain (loss)	$ 83,000	$ 0	$ 73,000	$ 0