Condensed Consolidated Statements of Stockholders' Deficit (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total
Beginning balance, shares at Dec. 31, 2019	3,932	12
Beginning balance, value at Dec. 31, 2019	$ 393	$ (1,721)	$ 182,514	$ (185,665)
Common stock issued, shares	37
Common stock issued	$ 1
Restricted stock issued, shares	6
Restricted stock issued
Common stock issued through market sales, shares	80
Common stock issued through market sales	$ 8		476
Common stock issued through ESPP, shares
Common stock issued through ESPP
Treasury stock purchased, shares
Treasury stock purchased
Extinguishment of Series A Shares			(828)
Beneficial Conversion Feature in connection with Series B Issuance			2,205
Amortization of Beneficial Conversion Feature			(2,205)
Stock-based compensation expense			418
Net loss				(6,494)
Ending balance, shares at Mar. 31, 2020	4,055	12
Ending balance, value at Mar. 31, 2020	$ 402	$ (1,721)	182,580	(192,159)
Beginning balance, shares at Dec. 31, 2019	3,932	12
Beginning balance, value at Dec. 31, 2019	$ 393	$ (1,721)	182,514	(185,665)
Net loss					(12,074)
Ending balance, shares at Jun. 30, 2020	4,055	19
Ending balance, value at Jun. 30, 2020	$ 402	$ (1,770)	182,980	(197,739)	(16,127)
Beginning balance, shares at Mar. 31, 2020	4,055	12
Beginning balance, value at Mar. 31, 2020	$ 402	$ (1,721)	182,580	(192,159)
Common stock issued, shares
Common stock issued
Treasury stock purchased, shares		7
Treasury stock purchased		$ (49)
Stock-based compensation expense			400
Net loss				(5,580)	(5,580)
Ending balance, shares at Jun. 30, 2020	4,055	19
Ending balance, value at Jun. 30, 2020	$ 402	$ (1,770)	182,980	(197,739)	(16,127)
Beginning balance, shares at Dec. 31, 2020	4,075	20
Beginning balance, value at Dec. 31, 2020	$ 402	$ (1,773)	184,404	(212,116)	(29,083)
Common stock issued, shares	9
Common stock issued			108
Restricted stock issued, shares	12
Restricted stock issued
Common stock issued through market sales, shares
Common stock issued through market sales
Common stock issued through ESPP, shares	36
Common stock issued through ESPP
Treasury stock purchased, shares
Treasury stock purchased
Extinguishment of Series A Shares
Beneficial Conversion Feature in connection with Series B Issuance
Amortization of Beneficial Conversion Feature
Stock-based compensation expense			286
Net loss				(4,207)
Ending balance, shares at Mar. 31, 2021	4,132	20
Ending balance, value at Mar. 31, 2021	$ 402	$ (1,773)	184,798	(216,323)
Beginning balance, shares at Dec. 31, 2020	4,075	20
Beginning balance, value at Dec. 31, 2020	$ 402	$ (1,773)	184,404	(212,116)	(29,083)
Net loss					(7,653)
Ending balance, shares at Jun. 30, 2021	4,142	20
Ending balance, value at Jun. 30, 2021	$ 402	$ (1,773)	185,349	(219,769)	(35,791)
Beginning balance, shares at Mar. 31, 2021	4,132	20
Beginning balance, value at Mar. 31, 2021	$ 402	$ (1,773)	184,798	(216,323)
Common stock issued, shares	10
Common stock issued
Treasury stock purchased, shares
Treasury stock purchased
Stock-based compensation expense			551
Net loss				(3,446)	(3,446)
Ending balance, shares at Jun. 30, 2021	4,142	20
Ending balance, value at Jun. 30, 2021	$ 402	$ (1,773)	$ 185,349	$ (219,769)	$ (35,791)