Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Treasury Stock [Member]	Total
Balance at Dec. 31, 2017		$ 35	$ 244,726	$ (226,770)	$ (500)	$ 17,491
Balance, shares at Dec. 31, 2017	5,659	35,182,589
Exercise of common stock options			98			$ 98
Exercise of common stock options, shares		99,937				99,937
Exercise of common stock warrants			46			$ 46
Exercise of common stock warrants, shares		30,000				30,000
Public offering of common shares, net of offering costs		$ 10	9,256			$ 9,266
Public offering of common shares, net of offering costs, shares		10,010,813
Stock based compensation			610			610
Net loss				(9,542)		(9,542)
Balance at Dec. 31, 2018		$ 45	254,736	(236,312)	(500)	17,969
Balance, shares at Dec. 31, 2018	5,659	45,323,339
Exercise of common stock options			9			$ 9
Exercise of common stock options, shares		12,500				12,500
Public offering of common shares, net of offering costs		$ 5	3,471			$ 3,476
Public offering of common shares, net of offering costs, shares		4,914,539
Stock based compensation			551			551
Net loss				(4,298)		(4,298)
Balance at Dec. 31, 2019		$ 50	$ 258,767	$ (240,610)	$ (500)	$ 17,707
Balance, shares at Dec. 31, 2019	5,659	50,250,378