Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal net operating loss carryforwards	$ 40,158	$ 31,943
State net operating loss carryforwards	4,541	4,762
Compensation	1,100	693
Allowances and reserves	1,007	7,539
State taxes	794	1,124
Credit carryforward	233	239
Deferred revenue	89	88
Property, plant and equipment	16	637
Other reserves - restructuring		5
Gross deferred tax assets	47,938	47,030
Intangible assets	(4,371)	(4,865)
Net Deferred tax assets	43,567	42,165
Less: Valuation allowance	(43,567)	(42,165)
Deferred tax asset-net valuation allowance