CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Series B Preferred Stock	At-the-market Issuance	Registered Direct Offering	Preferred Stock Series A Preferred Stock	Preferred Stock Series B Preferred Stock	Common Stock	Common Stock Series A Preferred Stock	Common Stock At-the-market Issuance	Common Stock Registered Direct Offering	Treasury Stock	Additional Paid-in Capital	Additional Paid-in Capital Series B Preferred Stock	Additional Paid-in Capital At-the-market Issuance	Additional Paid-in Capital Registered Direct Offering	Accumulated Other Comprehensive Income	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2020					7	0	184,133,384
Beginning balance at Dec. 31, 2020	$ 21,550				$ 0	$ 0	$ 1,841				$ (48)	$ 93,059				$ 0	$ (73,302)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation expense	833											833
Issuance of common stock for option exercises (in shares)							157,468
Issuance of common stock for stock option exercises	176						$ 2					174
Issuance of stock (in shares)						54,745			987,000	3,000,000
Issuance of stock		$ 4,954	$ 4,849	$ 21,204		$ 1			$ 10	$ 30			$ 4,953	$ 4,839	$ 21,174
Net loss	(7,077)																(7,077)
Ending balance (in shares) at Mar. 31, 2021					7	54,745	188,277,852
Ending balance at Mar. 31, 2021	46,489				$ 0	$ 1	$ 1,883				(48)	125,032				0	(80,379)
Beginning balance (in shares) at Dec. 31, 2020					7	0	184,133,384
Beginning balance at Dec. 31, 2020	21,550				$ 0	$ 0	$ 1,841				(48)	93,059				0	(73,302)
Increase (Decrease) in Stockholders' Equity
Foreign currency translation adjustment	0
Net loss	(33,029)
Ending balance (in shares) at Jun. 30, 2021					7	54,745	198,816,745
Ending balance at Jun. 30, 2021	116,409				$ 0	$ 1	$ 1,988				(48)	220,799				0	(106,331)
Beginning balance (in shares) at Mar. 31, 2021					7	54,745	188,277,852
Beginning balance at Mar. 31, 2021	46,489				$ 0	$ 1	$ 1,883				(48)	125,032				0	(80,379)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation expense	2,095											2,095
Issuance of stock (in shares)										10,000,000
Issuance of stock				$ 93,406						$ 100					$ 93,306
Issuance of common stock for stock option and warrant exercises (in shares)							538,893
Issuance of common stock for stock option and warrant exercises	371						$ 5					366
Foreign currency translation adjustment	0
Net loss	(25,952)																(25,952)
Ending balance (in shares) at Jun. 30, 2021					7	54,745	198,816,745
Ending balance at Jun. 30, 2021	116,409				$ 0	$ 1	$ 1,988				(48)	220,799				0	(106,331)
Beginning balance (in shares) at Dec. 31, 2021					7	54,745	199,502,183
Beginning balance at Dec. 31, 2021	95,818				$ 0	$ 1	$ 1,995				(48)	225,537				0	(131,667)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation expense	3,299											3,299
Issuance of common stock for option exercises (in shares)							277,323
Issuance of common stock for stock option exercises	180						$ 3					177
Issuance of stock (in shares)							15,973,420
Issuance of stock	49,851						$ 160					49,691
Net loss	(18,019)																(18,019)
Ending balance (in shares) at Mar. 31, 2022					7	54,745	215,752,926
Ending balance at Mar. 31, 2022	131,129				$ 0	$ 1	$ 2,158				(48)	278,704				0	(149,686)
Beginning balance (in shares) at Dec. 31, 2021					7	54,745	199,502,183
Beginning balance at Dec. 31, 2021	$ 95,818				$ 0	$ 1	$ 1,995				(48)	225,537				0	(131,667)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock for option exercises (in shares)	766,166
Foreign currency translation adjustment	$ 10
Net loss	(37,490)
Ending balance (in shares) at Jun. 30, 2022					0	54,745	216,271,262
Ending balance at Jun. 30, 2022	114,108				$ 0	$ 1	$ 2,163				(48)	281,139				10	(169,157)
Beginning balance (in shares) at Mar. 31, 2022					7	54,745	215,752,926
Beginning balance at Mar. 31, 2022	131,129				$ 0	$ 1	$ 2,158				(48)	278,704				0	(149,686)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation expense	2,079											2,079
Issuance of common stock for option exercises (in shares)							488,843
Issuance of common stock for stock option exercises	409						$ 5					404
Issuance of common stock upon restricted stock unit vesting, net (in shares)							26,378
Issuance of common stock upon restricted stock unit vesting, net	(48)											(48)
Series A convertible preferred stock conversion (in shares)					(7)			3,115
Foreign currency translation adjustment	10															10
Net loss	(19,471)																(19,471)
Ending balance (in shares) at Jun. 30, 2022					0	54,745	216,271,262
Ending balance at Jun. 30, 2022	$ 114,108				$ 0	$ 1	$ 2,163				$ (48)	$ 281,139				$ 10	$ (169,157)