Consolidated Statements of Changes in Equity (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]		Preferred Stock [Member] Series B Convertible Preferred Stock [Member]		Preferred Stock [Member] Series C Convertible Preferred Stock [Member]		Additional Paid-in Capital [Member]		Retained Earnings [Member]	Total
Balance at Dec. 31, 2019		[1]		[1]		[1]	$ 163,015		$ (157,632)	$ 5,383
Balance, shares at Dec. 31, 2019	261,075		17,303		34,370
Net loss									(6,691)	(6,691)
Exercise of pre-funded warrants		[1]					18			18
Exercise of pre-funded warrants, shares	990,427
Settlement of restricted stock units in shares of common stock		[1]
Settlement of restricted stock units in shares of common stock, shares	11,000
Issuance of common stock, net of $945 issuance costs		[1]					10,809			10,809
Issuance of common stock, net of $945 issuance costs, shares	770,813
Exercise of Warrants F		[1]					1,418			1,418
Exercise of warrants F, shares	191,107
Conversion of Series C Convertible Preferred Stock to common stock		[1]				[1]
Exercise of Unit Purchase Option		[1]					82			82
Exercise of unit purchase option, shares	16,906
Conversion of series C convertible preferred stock to common stock, shares	24,812				(32,027)
Share-based compensation related to restricted stock, restricted stock units and stock options award, net of forfeitures of 13,077 shares		[1]					261			261
Share-based compensation related to restricted stock, restricted stock units and stock options award, net of forfeitures of 19,036 shares	137,802
Balance at Sep. 30, 2020				[1]		[1]	175,603		(164,323)	11,280
Balance, shares at Sep. 30, 2020	2,403,942		17,303		2,343
Balance at Jun. 30, 2020				[2]		[2]	175,304		(162,090)	13,214
Balance, shares at Jun. 30, 2020	2,223,933		17,303		2,343
Net loss									(2,233)	(2,233)
Issuance of common stock, including at the market offering net of $2,024 issuance costs		[2]					158			158
Issuance of common shares at the market offering, net of $110 issuance costs, shares	39,540
Share-based compensation related to restricted stock, restricted stock units and stock options award, net of forfeitures of 13,077 shares		[2]					141			141
Share-based compensation related to restricted stock, restricted stock units and stock options award, net of forfeitures of 19,036 shares	140,469
Balance at Sep. 30, 2020				[1]		[1]	175,603		(164,323)	11,280
Balance, shares at Sep. 30, 2020	2,403,942		17,303		2,343
Balance at Dec. 31, 2020		[3]		[3]		[3]	180,339		(168,176)	12,163
Balance, shares at Dec. 31, 2020	3,284,322		17,303		2,343
Net loss									(10,821)	(10,821)
Exercise of Warrants F		[3]					8,120			8,120
Exercise of warrants F, shares	1,093,536
Exercise of Warrants G		[3]					1,349			1,349
Exercise of warrants G, shares	131,876
Conversion of Series C Convertible Preferred Stock to common stock		[3]		[3]		[3]		[3]			[3]
Conversion of series B convertible preferred stock to common stock, shares	207,528		(17,303)
Conversion of series C convertible preferred stock to common stock, shares	831				(625)
Issuance of common stock, including at the market offering net of $2,024 issuance costs	$ 1						25,241			25,242
Issuance of common shares at the market offering, net of $110 issuance costs, shares	3,133,775
Share-based compensation related to restricted stock, restricted stock units and stock options award, net of forfeitures of 13,077 shares							1,010			1,010
Share-based compensation related to restricted stock, restricted stock units and stock options award, net of forfeitures of 19,036 shares	3,166
Round up of shares due to reverse stock split effectuated on April 26, 2021
Round up of shares due to reverse stock split effectuated on April 26, 2021, shares	45,277
Balance at Sep. 30, 2021	$ 1					[4]	216,059		(178,997)	37,063
Balance, shares at Sep. 30, 2021	7,900,311				1,718
Balance at Jun. 30, 2021	$ 1					[4]	215,755		(174,926)	40,830
Balance, shares at Jun. 30, 2021	7,914,339				1,718
Net loss									(4,071)	(4,071)
Share-based compensation related to restricted stock, restricted stock units and stock options award, net of forfeitures of 13,077 shares		[4]					304			304
Share-based compensation related to restricted stock, restricted stock units and stock options award, net of forfeitures of 19,036 shares	(11,917)
Round up of shares due to reverse stock split effectuated on April 26, 2021		[4]
Round up of shares due to reverse stock split effectuated on April 26, 2021, shares	(2,111)
Balance at Sep. 30, 2021	$ 1					[4]	$ 216,059		$ (178,997)	$ 37,063
Balance, shares at Sep. 30, 2021	7,900,311				1,718

[1] Represents an amount less than $1 thousand

[2] Represents an amount less than $1 thousand

[3] Represents an amount less than $1 thousand

[4] Represents an amount less than $1 thousand