Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balance (in shares) at Dec. 31, 2020	116,231,000	0
Balance at Dec. 31, 2020	$ 116	$ 0	$ 781,397	$ (722,912)	$ 2,968	$ 61,569
Stock-based compensation	$ 0		1,786	0	0	1,786
Award of restricted stock units (in shares)	706,000	0
Award of restricted stock units	$ 1	$ 0	0	0	0	1
Return of common stock to pay withholding taxes on restricted stock (in shares)	0	67,000
Return of common stock to pay withholding taxes on restricted stock	$ 0	$ 0	(214)	0	0	(214)
Cancellation of treasury stock (in shares)	0	(67,000)
Cancellation of treasury stock	$ 0	$ 0	0	0	0	0
Other comprehensive loss	0			0	(1,938)	(1,938)
Net loss	$ 0			(17,340)	0	(17,340)
Issuance of common stock, net of issuance costs (in shares)	70,666,000	0
Issuance of common stock, net of issuance costs	$ 71	$ 0	129,251	0	0	129,322
Exercise of stock options and warrants (in shares)	45,114,000	0
Exercise of stock options and warrants	$ 45	$ 0	32,687	0	0	32,732
Balance (in shares) at Mar. 31, 2021	232,717,000	0
Balance at Mar. 31, 2021	$ 233	$ 0	944,907	(740,252)	1,030	205,918
Balance (in shares) at Dec. 31, 2021	235,219,000	0
Balance at Dec. 31, 2021	$ 235	$ 0	954,649	(785,374)	(264)	169,246
Stock-based compensation	$ 0		2,245	0	0	$ 2,245
Exercise of stock options (in shares)	30,000	0				30,001
Exercise of stock options	$ 0	$ 0	12	0	0	$ 12
Award of restricted stock units (in shares)	1,166,000	0
Award of restricted stock units	$ 1	$ 0	0	0	0	1
Return of common stock to pay withholding taxes on restricted stock (in shares)	0	436,000
Return of common stock to pay withholding taxes on restricted stock	$ 0	$ 0	(349)	0	0	(349)
Cancellation of treasury stock (in shares)	0	(436,000)
Cancellation of treasury stock	$ 0	$ 0	0	0	0	0
Other comprehensive loss	0	0	0	0	(1,202)	(1,202)
Net loss	$ 0	$ 0		(19,128)	0	(19,128)
Balance (in shares) at Mar. 31, 2022	236,415,000	0
Balance at Mar. 31, 2022	$ 236	$ 0	$ 956,557	$ (804,502)	$ (1,466)	$ 150,825