Inventories, Net and Significant Suppliers - Inventories, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Inventory Disclosure [Abstract]
Raw materials	$ 43,638	$ 33,059
Components	16,214	15,046
Work in process	1,847	5,860
Finished goods	105,178	80,119
Reserve for excess and obsolete inventory	(4,288)	(4,205)	$ (3,045)	$ (2,539)
Inventories, net	$ 162,589	$ 129,879