Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Inventory Disclosure [Abstract]
Raw materials	$ 33,853	$ 34,153
Work in process	2,522	2,262
Finished goods	2,881	1,917
Inventory, gross	39,256	38,332
Less: Allowance for excess and obsolete inventories	(757)	(714)	$ (579)	$ (363)
Total, net	$ 38,499	$ 37,618