Condensed Statements of Stockholders' Deficit - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, Adjusted Balance	Common Stock	Common Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Additional Paid-In Capital	Additional Paid-In Capital Cumulative Effect, Period of Adoption, Adjustment	Additional Paid-In Capital Cumulative Effect, Period of Adoption, Adjusted Balance	Accumulated Deficit	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjustment	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjusted Balance	Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss) Cumulative Effect, Period of Adoption, Adjusted Balance	Treasury Stock	Treasury Stock Cumulative Effect, Period of Adoption, Adjusted Balance
Beginning balance (in shares) at Dec. 31, 2020				25,916,168	25,916,168
Beginning balance at Dec. 31, 2020	$ (96,134)	$ (91,927)	$ (188,061)	$ 26	$ 26	$ 797,655	$ (93,475)	$ 704,180	$ (838,817)	$ 1,548	$ (837,269)	$ 0	$ 0	$ (54,998)	$ (54,998)
Increase (Decrease) in Stockholders' Equity
Exercise of stock options (in shares)				172,268
Exercise of stock options	2,668					2,668
Vesting of restricted stock units (in shares)				43,465
Vesting of restricted stock units	0
Vesting of ESPP Shares (in shares)				50,818
Vesting of ESPP Shares	1,183					1,183
Stock-based compensation	5,751					5,751
Net income (loss)	(90,935)								(90,935)
Ending balance (in shares) at Mar. 31, 2021				26,182,719
Ending balance at Mar. 31, 2021	(269,394)			$ 26		713,782			(928,204)			0		(54,998)
Beginning balance (in shares) at Dec. 31, 2021				60,879,496
Beginning balance at Dec. 31, 2021	$ (196,944)			$ 61		964,401			(1,106,377)			(31)		(54,998)
Increase (Decrease) in Stockholders' Equity
Exercise of stock options (in shares)	0
Vesting of restricted stock units (in shares)				55,286
Vesting of restricted stock units	$ 0
Vesting of ESPP Shares (in shares)				123,785
Vesting of ESPP Shares	431					431
Stock-based compensation	4,436					4,436
Other comprehensive loss	(232)											(232)
Net income (loss)	(56,731)								(56,731)
Ending balance (in shares) at Mar. 31, 2022				61,058,567
Ending balance at Mar. 31, 2022	$ (249,040)			$ 61		$ 969,268			$ (1,163,108)			$ (263)		$ (54,998)