CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands	Total	Common Stock	Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2021		201,988,662,000
Beginning balance at Dec. 31, 2021	$ 547,255	$ 2,020	$ 1,103,224	$ (614)	$ (557,375)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of warrants (in shares)		4,677,000
Issuance of common stock upon exercise of warrants	3		3
Non-cash stock-based compensation	4,044		4,044
Issuance of common stock under stock plans, net of taxes ( in shares)		240,617,000
Stock-based awards and related share issuances, net	(221)	$ (1)	(220)
Other comprehensive income (loss)	(973)			(973)
Net loss	(15,673)				(15,673)
Ending balance (in shares) at Mar. 31, 2022		201,752,722,000
Ending balance at Mar. 31, 2022	$ 534,435	$ 2,019	1,107,051	(1,587)	(573,048)
Beginning balance (in shares) at Dec. 31, 2022	237,166,625	237,166,625,000
Beginning balance at Dec. 31, 2022	$ 605,477	$ 2,372	1,259,527	(1,040)	(655,382)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Non-cash stock-based compensation	4,677		4,677
Issuance of common stock under stock plans, net of taxes ( in shares)		94,539,000
Stock-based awards and related share issuances, net	0	$ 1	(1)
Other comprehensive income (loss)	925			925
Net loss	$ (17,618)				(17,618)
Ending balance (in shares) at Mar. 31, 2023	237,261,164	237,261,164,000
Ending balance at Mar. 31, 2023	$ 593,461	$ 2,373	$ 1,264,203	$ (115)	$ (673,000)