Investment in Joint Venture - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Equity Method Investments [Line Items]
Net sales	$ 619,793	$ 584,954	$ 405,443
Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Investment in joint venture	49.00%
Net sales	$ 200	100	200
Amount due from joint venture	$ 100	$ 100	$ 200
Wuxi Weifu Autocam Precision Machinery Company, Ltd. [Member]
Schedule of Equity Method Investments [Line Items]
Investment in joint venture	49.00%