Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Comprehensive Deficit [Member]
BALANCE at Dec. 31, 2016	$ 3,059		$ 12	$ 229,275	$ (226,228)
BALANCE, Shares at Dec. 31, 2016			12,298,000
Non-cash compensation recognized on stock options and ESPP	44			44
Restricted stock grants, net of cancellations	1,127			1,127
Restricted stock grants, net of cancellations, shares			(69,000)
Cancellation of shares for payment of withholding tax	(171)			(171)
Cancellation of shares for payment of withholding tax, shares			(126,000)
Employee stock purchase plan	3			3
Employee stock purchase plan, shares			4,000
Preferred shares issued in stock offering, net of offering costs	5,213			5,213
Preferred shares issued in stock offering, net of offering costs, shares		3,000
Common shares issued in stock offering, net of offering costs	1,992		$ 2	1,990
Common shares issued in stock offering, net offering costs, shares			2,162,000
Issuance of warrants in stock offering	64			64
Preferred shares issued with debt/converted to common shares	(103)			(103)
Preferred shares issued with debt conversion/converted to common shares, shares		3,000
Warrant repricing				44	(44)
Net loss	(6,661)				(6,661)
Comprehensive loss	(6,661)
BALANCE at Dec. 31, 2017	$ 4,567		$ 14	237,486	(232,933)
BALANCE, Shares at Dec. 31, 2017	5,500	6,000
BALANCE, Shares at Dec. 31, 2017	14,268,765		14,269,000
Non-cash compensation recognized on stock options and ESPP	$ 36			36
Restricted stock grants, net of cancellations	899		$ 1	898
Restricted stock grants, net of cancellations, shares			1,124,000
Cancellation of shares for payment of withholding tax	(209)			(209)
Cancellation of shares for payment of withholding tax, shares			(94,000)
Employee stock purchase plan	5			5
Employee stock purchase plan, shares			5,000
Common shares issued in stock offering, net of offering costs	17,600		$ 9	17,591
Common shares issued in stock offering, net offering costs, shares			9,267,000
Issuance of warrants in stock offering	(6,792)			(6,792)
Preferred shares issued with debt/converted to common shares			$ 4	(4)
Preferred shares issued with debt conversion/converted to common shares, shares		(5,000)	3,645,000
Exercise of warrants, shares			26,000
Reclassification of warrants previously classified as liabilities to equity	7,604			7,604
Warrant repricing				11	(11)
Canadian tax adjustments from prior period	(2)				(2)
Preferred stock dividends	(404)				(404)
Net loss	(2,740)
Comprehensive loss	(2,741)				(2,741)
BALANCE at Dec. 31, 2018	$ 20,563		$ 28	$ 256,626	$ (236,091)
BALANCE, Shares at Dec. 31, 2018	1,345	1,000
BALANCE, Shares at Dec. 31, 2018	28,241,129		28,242,000