Fair Value Measurements - Additional Information (Detail) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]
Derivative maturities	4 years
Effective portion of change in fair value of foreign currency forward contracts	$ (2,237,000)	$ 1,029,000
Long-term debt, fair market value	332,163,000	331,941,000
Long-term debt, carrying value	$ 296,179,000	297,094,000
Maximum
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]
Maturities of forward contracts	12 months
Foreign Exchange Contracts
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]
Derivative maturities	4 years
Notional amount of the foreign currency derivative instruments	$ 145,770,000	$ 89,414,000