CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	Total
Beginning balance (in shares) at Dec. 31, 2021	201,988,662
Beginning balance at Dec. 31, 2021	$ 2,020	$ 1,103,224	$ (614)	$ (557,375)	$ 547,255
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock and common stock warrants, net of issuance costs (in shares)	33,333,336
Issuance of common stock and common stock warrants, net of issuance costs	$ 333	138,675			139,008
Issuance of common stock upon exercise of warrants (in shares)	4,677
Issuance of common stock upon exercise of warrants		3			3
Non-cash stock-based compensation		12,625			12,625
Stock-based awards and related share issuances, net ( in shares)	1,895,057
Stock-based awards and related share issuances, net	$ 19	206			225
Other comprehensive income (loss)			(1,554)		(1,554)
Net loss				(72,620)	(72,620)
Ending balance (in shares) at Sep. 30, 2022	237,221,732
Ending balance at Sep. 30, 2022	$ 2,372	1,254,733	(2,168)	(629,995)	624,942
Beginning balance (in shares) at Jun. 30, 2022	235,165,951
Beginning balance at Jun. 30, 2022	$ 2,353	1,249,880	(2,256)	(586,209)	663,768
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Non-cash stock-based compensation		4,361			4,361
Stock-based awards and related share issuances, net ( in shares)	2,055,781
Stock-based awards and related share issuances, net	$ 19	492			511
Other comprehensive income (loss)			88		88
Net loss				(43,786)	(43,786)
Ending balance (in shares) at Sep. 30, 2022	237,221,732
Ending balance at Sep. 30, 2022	$ 2,372	1,254,733	(2,168)	(629,995)	$ 624,942
Beginning balance (in shares) at Dec. 31, 2022	237,166,625				237,166,625
Beginning balance at Dec. 31, 2022	$ 2,372	1,259,527	(1,040)	(655,382)	$ 605,477
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Non-cash stock-based compensation		12,752			12,752
Stock-based awards and related share issuances, net ( in shares)	3,086,082
Stock-based awards and related share issuances, net	$ 31	(31)			0
Other comprehensive income (loss)			$ 1,040		1,040
Net loss				(47,738)	$ (47,738)
Ending balance (in shares) at Sep. 30, 2023	240,252,707				240,252,707
Ending balance at Sep. 30, 2023	$ 2,403	1,272,248		(703,120)	$ 571,531
Beginning balance (in shares) at Jun. 30, 2023	237,647,431
Beginning balance at Jun. 30, 2023	$ 2,377	1,268,142		(687,420)	583,099
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Non-cash stock-based compensation		4,132			4,132
Stock-based awards and related share issuances, net ( in shares)	2,605,276
Stock-based awards and related share issuances, net	$ 26	(26)
Net loss				(15,700)	$ (15,700)
Ending balance (in shares) at Sep. 30, 2023	240,252,707				240,252,707
Ending balance at Sep. 30, 2023	$ 2,403	$ 1,272,248		$ (703,120)	$ 571,531