Inventories - Schedule of Inventory (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Raw materials	$ 3,316	$ 5,049
Finished goods	6,598	10,016
Reserve for excess, obsolete, and slow moving inventories	(4,196)	(5,596)
Inventories, net	5,718	9,469
Increase in gross inventory levels	(5,200)	5,000
Provision for slow-moving and obsolete inventories	$ (1,400)	$ 3,281	$ 1,739