Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Total
Balance at Dec. 31, 2018	$ 287	$ (1,680)	$ 175,820	$ (158,981)	$ 15,446
Balance, shares at Dec. 31, 2018	2,877,000	7,000
Common stock issued	$ 1				1
Common stock issued, shares	9,000
Restricted stock issued
Restricted stock issued, shares
Common stock issued through offering, net of expenses	$ 94		5,868		5,962
Common stock issued through offering, net of expenses, shares	933,000
Common stock issued through market sales, net of expenses
Common stock issued through market sales, net of expenses, shares
Beneficial Conversion Feature in connection with Series B Issuance
Amortization of Beneficial Conversion Feature
Treasury stock purchased		$ (32)			(32)
Treasury stock purchased, shares		3,000
Stock-based compensation expense			266		266
Adoption of ASC 842				55	55
Net loss				(3,326)	(3,326)
Balance at Mar. 31, 2019	$ 382	$ (1,712)	181,954	(162,252)	18,372
Balance, shares at Mar. 31, 2019	3,819,000	10,000
Balance at Dec. 31, 2018	$ 287	$ (1,680)	175,820	(158,981)	15,446
Balance, shares at Dec. 31, 2018	2,877,000	7,000
Net loss					(26,740)
Balance at Dec. 31, 2019	$ 393	$ (1,721)	182,514	(185,665)	(4,479)
Balance, shares at Dec. 31, 2019	3,932,000	12,000
Balance at Mar. 31, 2019	$ 382	$ (1,712)	181,954	(162,252)	18,372
Balance, shares at Mar. 31, 2019	3,819,000	10,000
Common stock issued	$ 1		72		73
Common stock issued, shares	10,000
Treasury stock purchased
Treasury stock purchased, shares
Stock-based compensation expense			205		205
Net loss				(5,304)	(5,304)
Balance at Jun. 30, 2019	$ 383	$ (1,712)	182,231	(167,556)	13,346
Balance, shares at Jun. 30, 2019	3,829,000	10,000
Common stock issued
Treasury stock purchased
Treasury stock purchased, shares
Stock-based compensation expense			205		205
Dividends accrued			(75)		(75)
Net loss				(7,446)	(7,446)
Balance at Sep. 30, 2019	$ 383	$ (1,712)	182,361	(175,002)	6,030
Balance, shares at Sep. 30, 2019	3,829,000	10,000
Common stock issued
Common stock issued, shares	5,000
Common stock issued through market sales, net of expenses	$ 10		218		228
Common stock issued through market sales, net of expenses, shares	98,000
Treasury stock purchased		$ (9)			(9)
Treasury stock purchased, shares		2,000
Stock-based compensation expense			289		289
Dividends accrued			(354)		(354)
Net loss				(10,663)	(10,663)
Balance at Dec. 31, 2019	$ 393	$ (1,721)	182,514	(185,665)	(4,479)
Balance, shares at Dec. 31, 2019	3,932,000	12,000
Common stock issued	$ 1				1
Common stock issued, shares	37,000
Restricted stock issued
Restricted stock issued, shares	6,000
Common stock issued through offering, net of expenses
Common stock issued through offering, net of expenses, shares
Common stock issued through market sales, net of expenses	$ 8		476		484
Common stock issued through market sales, net of expenses, shares	80,000
Extinguishment of Series A Shares			(828)		(828)
Beneficial Conversion Feature in connection with Series B Issuance			2,205		2,205
Amortization of Beneficial Conversion Feature			(2,205)		(2,205)
Treasury stock purchased
Treasury stock purchased, shares
Stock-based compensation expense			418		418
Adoption of ASC 842
Net loss				(6,494)	(6,494)
Balance at Mar. 31, 2020	$ 402	$ (1,721)	182,580	(192,159)	(10,898)
Balance, shares at Mar. 31, 2020	4,055,000	12,000
Balance at Dec. 31, 2019	$ 393	$ (1,721)	182,514	(185,665)	(4,479)
Balance, shares at Dec. 31, 2019	3,932,000	12,000
Net loss					(26,451)
Balance at Dec. 31, 2020	$ 402	$ (1,773)	184,404	(212,116)	(29,083)
Balance, shares at Dec. 31, 2020	4,075,000	20,000
Balance at Mar. 31, 2020	$ 402	$ (1,721)	182,580	(192,159)	(10,898)
Balance, shares at Mar. 31, 2020	4,055,000	12,000
Common stock issued
Common stock issued, shares
Treasury stock purchased		$ (49)			(49)
Treasury stock purchased, shares		7,000
Stock-based compensation expense			400		400
Net loss				(5,580)	(5,580)
Balance at Jun. 30, 2020	$ 402	$ (1,770)	182,980	(197,739)	(16,127)
Balance, shares at Jun. 30, 2020	4,055,000	19,000
Common stock issued
Common stock issued, shares	5,000
Stock-based compensation expense			563		563
Dividends accrued
Net loss				(6,234)	(6,234)
Balance at Sep. 30, 2020	$ 402	$ (1,770)	183,543	(203,973)	(21,798)
Balance, shares at Sep. 30, 2020	4,060,000	19,000
Common stock issued
Common stock issued, shares	15,000
Common stock issued through market sales, net of expenses
Treasury stock purchased		$ (3)			(3)
Treasury stock purchased, shares		1,000
Stock-based compensation expense			861		861
Dividends accrued
Net loss				(8,143)	(8,143)
Balance at Dec. 31, 2020	$ 402	$ (1,773)	$ 184,404	$ (212,116)	$ (29,083)
Balance, shares at Dec. 31, 2020	4,075,000	20,000