Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Tax benefit of operating loss carry forward	$ 8,088	$ 7,942
Reserves and allowances	2	1
Accrued expenses	57	73
Charitable contributions	8	134
Stock-based compensation	701	802
Fixed assets	(37)	0
Goodwill	292	144
Intangible amortization	50	61
Texas margin tax temporary credit	209	233
Total deferred tax assets	9,370	9,390
Valuation allowance	(9,370)	(9,390)
Net deferred tax assets	$ 0	$ 0