Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Mar. 31, 2014	Dec. 31, 2013
Fair Value Of Financial Instruments [Line Items]
Cash and cash equivalents	$ 30,763	$ 18,162	$ 18,039		$ 22,661
Cash held internationally, principally in Netherlands, China, Great Britain, and Canada	24,000	$ 11,700
Restricted cash held outside of United States	$ 4,300
Foreign Exchange Contract [Member]
Fair Value Of Financial Instruments [Line Items]
U.S. dollar-denominated transaction total				$ 5,500