CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total		Common Stock	Additional Paid-in Capital	AOCI Attributable to Parent	Retained Earnings
Beginning balance (in shares) at Dec. 31, 2020			70,583
Beginning balance at Dec. 31, 2020	$ 280,043		$ 71	$ 578,599	$ 4	$ (298,631)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under offering, net of issuance cost (in shares)			5,324
Issuance of common stock under offering, net of issuance costs	134,570		$ 5	134,565
Issuance of common stock upon exercise of stock options (in shares)			1,001
Issuance of common stock upon exercise of stock options	5,907		$ 1	5,906
Vesting of common stock from early exercises (in shares)			5
Vesting of common stock from early exercises	41			41
Stock-based compensation expense	6,582			6,582
Comprehensive income (loss)	(22)				(22)
Net loss	(27,544)					(27,544)
Ending balance (in shares) at Mar. 31, 2021			76,913
Ending balance at Mar. 31, 2021	399,577		$ 77	725,693	(18)	(326,175)
Beginning balance (in shares) at Dec. 31, 2021			77,962
Beginning balance at Dec. 31, 2021	$ 335,647	[1]	$ 78	754,664	(129)	(418,966)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)	125		125
Issuance of common stock upon exercise of stock options	$ 668		$ 0	668
Stock-based compensation expense	7,820			7,820
Comprehensive income (loss)	(548)				(548)
Net loss	(32,450)					(32,450)
Ending balance (in shares) at Mar. 31, 2022			78,087
Ending balance at Mar. 31, 2022	$ 311,137		$ 78	$ 763,152	$ (677)	$ (451,416)

[1] The condensed consolidated balance sheet as of December 31, 2021 has been derived from the audited financial statements as of that date.