Consolidated Statements of Changes in Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Preferred Stock [Member]	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income [Member]	Total
Beginning balance, shares at Dec. 31, 2018	949	13,259
Beginning balance, value at Dec. 31, 2018	$ 1,843	$ 133	$ (362)	$ 56,609	$ (59,242)	$ (43)
Conversion of preferred shares to common shares, shares converted
Conversion of preferred shares to common shares, value
Exercise of stock options, shares		293					294
Exercise of stock options, value		$ 3		236
Public offering, shares
Public offering, value
Stock-based compensation				47
Preferred stock dividends declared, net of waived penalties by shareholders				(133)
Net income (loss)					4,465		$ 4,465
Ending balance, shares at Dec. 31, 2019	949	13,552
Ending balance, value at Dec. 31, 2019	$ 1,843	$ 136	(362)	56,759	(54,777)	(43)	$ 3,556
Conversion of preferred shares to common shares, shares converted	(949)	1,068
Conversion of preferred shares to common shares, value	$ (1,843)	$ 10		1,833
Exercise of stock options, shares		343					343
Exercise of stock options, value		$ 3		206
Public offering, shares		2,465
Public offering, value		$ 25		18,146
Stock-based compensation				322
Preferred stock dividends declared, net of waived penalties by shareholders				(79)
Net income (loss)					(6,518)		$ (6,518)
Ending balance, shares at Dec. 31, 2020		17,428
Ending balance, value at Dec. 31, 2020		$ 174	$ (362)	$ 77,187	$ (61,295)	$ (43)	$ 15,661