Nature of Business and Going Concern (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended
Feb. 01, 2019	Dec. 31, 2019	Dec. 31, 2018
Going Concern [Line Items]
Net Cash Provided by (Used in) Operating Activities		$ (9,060)	$ (7,826)
Accumulated deficit		(144,031)	(131,256)
Net loss		$ (12,775)	$ (9,888)
Bridge Bank [Member] \| Loan And Security Agreement [Member] \| Term Loan [Member]
Going Concern [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 12,500
Shares, Issued	39,130
Shares Issued, Price Per Share	$ 6.80
Debt Instrument, Basis Spread on Variable Rate	4.75%
Debt Instrument, Interest Rate, Stated Percentage	1.00%

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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