CONSOLIDATED STATEMENTS OF STOCKHOLDERS' DEFICIT - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]
Beginning balance, value at Dec. 31, 2020	$ (124,001)	$ 6	$ 754,938	$ (878,945)
Beginning balance, shares at Dec. 31, 2020		5,996,000
Shares issued for sale of common stock, net of cost	150,899	$ 2	150,897
Shares issued for sale of common stock, net of cost, shares		1,857,000
Shares issued for exercise of warrants and options, net of cashless exercises	50		50
Shares issued for exercise of warrants and options, net of cashless exercises (in shares)		10,000
Shares issued for vested restricted stock units (in shares)		1,000
Share-based compensation	2,957		2,957
Net loss	(39,383)			(39,383)
Ending balance, value at Mar. 31, 2021	(9,478)	$ 8	908,842	(918,328)
Ending balance, shares at Mar. 31, 2021		7,864,000
Beginning balance, value at Dec. 31, 2021	$ (93,621)	$ 9	957,730	(1,051,360)
Beginning balance, shares at Dec. 31, 2021	8,598,000	8,598,000
Shares issued for vested restricted stock units (in shares)		71,000
Share-based compensation	$ 2,062		2,062
Net loss	(49,021)			(49,021)
Ending balance, value at Mar. 31, 2022	$ (140,580)	$ 9	$ 959,792	$ (1,100,381)
Ending balance, shares at Mar. 31, 2022	8,669,000	8,669,000