Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Accrued legal and professional fees	$ 215	$ 160
Accrued payroll and related benefits	360	435
Accrued sales commissions	32	115
Accrued severance	7	188
Accrued restructuring	24	156
Accrued warranty reserve	195	258	$ 174
Accrued liabilities	179	73
Total accrued liabilities	$ 1,012	$ 1,385