CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Capital in Excess of Par Value	Other Comprehensive Income Loss	Accumulated Deficit	Total
Beginning balance at Dec. 31, 2018	$ 1	$ 170,391	$ 21	$ (99,135)	$ 71,278
Beginning balance (in shares) at Dec. 31, 2018	124,642,593
Stock issued in connection with RSU vesting (in shares)	100,000
Stock issued in connection with warrant exercises		10,616			$ 10,616
Stock issued in connection with warrant exercises (in shares)	11,293,211
Stock issued in connection with option exercises (in shares)	39,988				75,000
Equity-based compensation		3,540			$ 3,540
Stock issued in connection with litigation expense		1,891			1,891
Stock issued in connection with litigation expense (in shares)	990,000
Stock issued in connection with Panacea investment		1,297			1,297
Stock issued in connection with Panacea investment (in shares)	1,297,017
Unrealized gain (loss) on short-term investment securities			207		207
Reclassification of losses (gains) to net loss			(221)		(221)
Net loss				(26,558)	(26,558)
Ending balance at Dec. 31, 2019	$ 1	187,735	7	(125,693)	62,050
Ending balance (in shares) at Dec. 31, 2019	138,362,809
Stock issued in connection with RSU vesting (in shares)	552,800
Stock issued in connection with option exercises		50			$ 50
Stock issued in connection with option exercises (in shares)	146,081				399,000
Equity-based compensation		1,654			$ 1,654
Unrealized gain (loss) on short-term investment securities			72		72
Reclassification of losses (gains) to net loss			(5)		(5)
Net loss				(19,711)	(19,711)
Ending balance at Dec. 31, 2020	$ 1	189,439	74	(145,404)	44,110
Ending balance (in shares) at Dec. 31, 2020	139,061,690
Stock issued in connection with RSU vesting, net of shares withheld for taxes		(469)			(469)
Stock issued in connection with RSU vesting, net of shares withheld for taxes (in shares)	1,534,361
Stock issued in connection with warrant exercises	$ 1	11,781			11,782
Stock issued in connection with warrant exercises (in shares)	11,293,211
Stock issued in connection with option exercises		1,307			$ 1,307
Stock issued in connection with option exercises (in shares)	983,613				984,000
Stock issued in connection with capital raise		38,206			$ 38,206
Stock issued in connection with capital raise (in shares)	10,000,000
Equity-based compensation		3,983			3,983
Unrealized gain (loss) on short-term investment securities			(236)		(236)
Net loss				(32,609)	(32,609)
Ending balance at Dec. 31, 2021	$ 2	$ 244,247	$ (162)	$ (178,013)	$ 66,074
Ending balance (in shares) at Dec. 31, 2021	162,872,875