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, 2016		$ 32	$ 239,915	$ (218,987)	$ (500)	$ 20,460
Balance, shares at Dec. 31, 2016	5,659	31,788,582
Exercise of common stock options			140			140
Exercise of common stock options, shares		94,007
Public offering of common shares, net of offering costs		$ 3	4,043			4,046
Public offering of common shares, net of offering costs, shares		3,300,000
Stock based compensation			628			628
Net loss				(7,783)		(7,783)
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 options			46			$ 46
Exercise of common stock options, shares		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