Unaudited Condensed Statements of Changes in Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Preferred Stock [Member] Series A Convertible Preferred Stock [Member] Underwritten Public Offering [Member]	Preferred Stock [Member] Series A Convertible Preferred Stock [Member] January 2021 Inducement Warrants [Member]	Preferred Stock [Member] Series A Convertible Preferred Stock [Member] Warrants to Purchase Common Stock [Member]	Preferred Stock [Member] Series A Convertible Preferred Stock [Member] Exchange Warrants [Member]	Preferred Stock [Member] Series A Convertible Preferred Stock [Member] Conversion of Facility Notes into Series B-2 Preferred Stock [Member]	Preferred Stock [Member] Series A Convertible Preferred Stock [Member] Conversion of Series B-2 Preferred Stock into Common Stock [Member]	Preferred Stock [Member] Series A Convertible Preferred Stock [Member]	Preferred Stock [Member] Series B-1 Convertible Preferred Stock [Member] Underwritten Public Offering [Member]	Preferred Stock [Member] Series B-1 Convertible Preferred Stock [Member] January 2021 Inducement Warrants [Member]	Preferred Stock [Member] Series B-1 Convertible Preferred Stock [Member] Warrants to Purchase Common Stock [Member]	Preferred Stock [Member] Series B-1 Convertible Preferred Stock [Member] Exchange Warrants [Member]	Preferred Stock [Member] Series B-1 Convertible Preferred Stock [Member] Conversion of Facility Notes into Series B-2 Preferred Stock [Member]	Preferred Stock [Member] Series B-1 Convertible Preferred Stock [Member] Conversion of Series B-2 Preferred Stock into Common Stock [Member]	Preferred Stock [Member] Series B-1 Convertible Preferred Stock [Member]	Preferred Stock [Member] Series B-2 Convertible Preferred Stock [Member] Underwritten Public Offering [Member]	Preferred Stock [Member] Series B-2 Convertible Preferred Stock [Member] January 2021 Inducement Warrants [Member]	Preferred Stock [Member] Series B-2 Convertible Preferred Stock [Member] Warrants to Purchase Common Stock [Member]	Preferred Stock [Member] Series B-2 Convertible Preferred Stock [Member] Exchange Warrants [Member]	Preferred Stock [Member] Series B-2 Convertible Preferred Stock [Member] Conversion of Facility Notes into Series B-2 Preferred Stock [Member]	Preferred Stock [Member] Series B-2 Convertible Preferred Stock [Member] Conversion of Series B-2 Preferred Stock into Common Stock [Member]	Preferred Stock [Member] Series B-2 Convertible Preferred Stock [Member]	Preferred Stock [Member] Undesignated Preferred Stock [Member]	Undesignated Preferred Stock [Member] Underwritten Public Offering [Member]	Undesignated Preferred Stock [Member] January 2021 Inducement Warrants [Member]	Undesignated Preferred Stock [Member] Warrants to Purchase Common Stock [Member]	Undesignated Preferred Stock [Member] Exchange Warrants [Member]	Undesignated Preferred Stock [Member] Conversion of Facility Notes into Series B-2 Preferred Stock [Member]	Undesignated Preferred Stock [Member] Conversion of Series B-2 Preferred Stock into Common Stock [Member]	Undesignated Preferred Stock [Member]	Common Stock [Member] Underwritten Public Offering [Member]	Common Stock [Member] January 2021 Inducement Warrants [Member]	Common Stock [Member] Warrants to Purchase Common Stock [Member]	Common Stock [Member] Exchange Warrants [Member]	Common Stock [Member] Conversion of Facility Notes into Series B-2 Preferred Stock [Member]	Common Stock [Member] Conversion of Series B-2 Preferred Stock into Common Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member] Underwritten Public Offering [Member]	Additional Paid-in Capital [Member] January 2021 Inducement Warrants [Member]	Additional Paid-in Capital [Member] Warrants to Purchase Common Stock [Member]	Additional Paid-in Capital [Member] Exchange Warrants [Member]	Additional Paid-in Capital [Member] Conversion of Facility Notes into Series B-2 Preferred Stock [Member]	Additional Paid-in Capital [Member] Conversion of Series B-2 Preferred Stock into Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member] Underwritten Public Offering [Member]	Retained Earnings [Member] January 2021 Inducement Warrants [Member]	Retained Earnings [Member] Warrants to Purchase Common Stock [Member]	Retained Earnings [Member] Exchange Warrants [Member]	Retained Earnings [Member] Conversion of Facility Notes into Series B-2 Preferred Stock [Member]	Retained Earnings [Member] Conversion of Series B-2 Preferred Stock into Common Stock [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Underwritten Public Offering [Member]	January 2021 Inducement Warrants [Member]	Warrants to Purchase Common Stock [Member]	Exchange Warrants [Member]	Conversion of Facility Notes into Series B-2 Preferred Stock [Member]	Conversion of Series B-2 Preferred Stock into Common Stock [Member]	Total
Balance at Dec. 31, 2020							$ 0							$ 0							$ 0								$ 0							$ 0							$ 192,062							$ (258,474)								$ (66,412)
Net income (loss)							0							0							0								0							0							0							(10,296)								(10,296)
Stock-based compensation expense							0							0							0								0							0							675							0								675
Issuance of common stock in exchange for consulting services							0							0							0								0							0							82							0								82
Issuance of common stock in connection with Public Offering, net of discounts and commissions	$ 0							$ 0							$ 0								$ 0							$ 1							$ 49,284							$ 0								$ 49,285
Issuance of common stock in connection with the exercise of warrants in the Inducement Transaction, net of discounts and commissions		$ 0							$ 0							$ 0								$ 0							$ 1							$ 40,390							$ 0								$ 40,391
Issuance of common stock in connection with the exercise of common stock warrants			$ 0							$ 0							$ 0								$ 0							$ 0							$ 25,593							$ 0								$ 25,593
Fair value of warrants issued		0		$ 0					0		$ 0					0		$ 0						0		$ 0					0		$ 0					38,437		$ 15,990					0		$ 0						38,437		$ 15,990
Issuance of stock as a result of conversion					$ 0	$ 0						$ 0	$ 0						$ 29,056	$ (29,056)							$ 0	$ 0						$ 0	$ 1						$ 0	$ 29,055						$ 0	$ 0							$ 0	$ 29,056
Deemed dividend related the Inducement Transaction		$ 0							$ 0							$ 0								$ 0							$ 0							$ (37,444)							$ 0								$ (37,444)
Offering expenses charged to equity							0							0							0								0							0							(1,106)							0								(1,106)
Balance at Mar. 31, 2021							$ 0							$ 0							$ 0								$ 0							3							353,018							(268,770)								84,251
Balance at Dec. 31, 2021																						$ 0														4							396,957							(267,029)	$ (2,814)							127,118
Net income (loss)																						0														0							0							(1,864)	0							(1,864)
Stock-based compensation expense																						0														0							918							0	0							918
Shares repurchased as part of the Share Repurchase Program																						0																					0							0	(4,722)							(4,723)
Shares repurchased as part of the Share Repurchase Program																																				(1)
Issuance of common stock in exchange for consulting services																						0														0							50							0	0							50
Balance at Mar. 31, 2022																						$ 0														$ 3							$ 397,925							$ (268,893)	$ (7,536)							$ 121,499