Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Preferred Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Accumulated Deficit [Member]	Total
Beginning Balance at Dec. 31, 2017			$ 149,425	$ (264)	$ (145,055)	$ 4,106
Beginning Balance (in shares) at Dec. 31, 2017	1,467,052	5,559		3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance common stock in equity raise, net of offering cost			2,700			2,700
Issuance common stock in equity raise, net of offering cost (in shares)	522,876
Stock-based compensation			314			314
Stock-based compensation (in shares)	20,097
Cumulative effect of the changes related to adoption of ASC 606					3,245	3,245
Net loss					(3,775)	(3,775)
Ending Balance at Sep. 30, 2018			152,439	$ (264)	(145,585)	6,590
Ending Balance (in shares) at Sep. 30, 2018	2,010,025	5,559		3
Beginning Balance at Jun. 30, 2018			152,411	$ (264)	(143,694)	8,453
Beginning Balance (in shares) at Jun. 30, 2018	2,010,025	5,559		3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation			28			28
Net loss					(1,891)	(1,891)
Ending Balance at Sep. 30, 2018			152,439	$ (264)	(145,585)	6,590
Ending Balance (in shares) at Sep. 30, 2018	2,010,025	5,559		3
Beginning Balance at Dec. 31, 2018			152,445	$ (264)	(140,083)	12,098
Beginning Balance (in shares) at Dec. 31, 2018	2,010,025	5,559		3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock and prefunded common stock warrants, net of offering cost			787			787
Issuance of common stock and prefunded common stock warrants, net of offering cost (in shares)	221,000
Issuance of common stock, net of offering cost / At-the-market offering			523			523
Issuance of common stock, net of offering cost / At-the-market offering (in shares)	239,359
Exercise of prefunded common stock warrants
Exercise of prefunded common stock warrants (in shares)	201,961
Warrant exercise
Warrant exercise (in shares)	33,333
Exchange of common shares for prefunded warrants
Exchange of common shares for prefunded warrants (in shares)	(115,269)
Fractional shares adjusted for reverse split
Fractional shares adjusted for reverse split (in shares)	3,371
Stock-based compensation			329			329
Net loss					(5,156)	(5,156)
Ending Balance at Sep. 30, 2019			154,084	$ (264)	(145,239)	8,581
Ending Balance (in shares) at Sep. 30, 2019	2,593,780	5,559		3
Beginning Balance at Jun. 30, 2019			153,347	$ (264)	(141,876)	11,207
Beginning Balance (in shares) at Jun. 30, 2019	2,321,088	5,559		3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock, net of offering cost / At-the-market offering			523			523
Issuance of common stock, net of offering cost / At-the-market offering (in shares)	239,359
Warrant exercise
Warrant exercise (in shares)	33,333
Stock-based compensation			214			214
Net loss					(3,363)	(3,363)
Ending Balance at Sep. 30, 2019			$ 154,084	$ (264)	$ (145,239)	$ 8,581
Ending Balance (in shares) at Sep. 30, 2019	2,593,780	5,559		3