Income Taxes (Details 1) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets:
Net operating loss carryforwards	$ 23,520	$ 31,935
Inventory and other allowances	12	16
Charitable contribution carryforwards	2	5
Excess (tax) book depreciation	577	805
Excess (tax) book amortization	53	69
Share-based compensation	885	1,328
Other accrued costs	167	219
Total deferred tax assets	25,216	34,377
Less: Valuation allowance	$ (25,216)	$ (34,377)