Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Account payable	$ 1,004	$ 1,127
Accrued franchise taxes	342	342
Accrued directors fees	45	55
Accrued professional fees	76	135
Warranty reserve	187	27
Accrued salaries and related	1,415	1,262
Other accrued expenses	183	216
Total accounts payable and accrued expenses	$ 3,252	$ 3,164