Consolidated Statements of Stockholders' Deficit - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive (Loss) Income	Accumulated Deficit
Beginning balance at Dec. 31, 2019	$ 38,252	$ 1,541	$ 877,300	$ 39	$ (840,628)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(182,814)				(182,814)
Other comprehensive loss	(36)			(36)
Exercise of stock options, net	1,814	5	1,809
Employee stock purchase plan sales, net	632	3	629
Issuance of common stock, net	93,279	220	93,059
Issuance of pre-funded warrants	14,817		14,817
Stock-based compensation expense	14,794		14,794
Ending balance at Dec. 31, 2020	(19,262)	1,769	1,002,408	3	(1,023,442)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(184,062)				(184,062)
Other comprehensive loss	174			174
Exercise of stock options, net	13,805	33	13,772
Employee stock purchase plan sales, net	1,989	3	1,986
Issuance of common stock, net	45,730	38	45,692
Stock-based compensation expense	34,640		34,640
Ending balance at Dec. 31, 2021	(106,986)	1,843	1,098,498	177	(1,207,504)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(247,116)				(247,116)
Other comprehensive loss	(151)			(151)
Exercise of stock options, net	12,090	30	12,060
Employee stock purchase plan sales, net	2,862	3	2,859
Issuance of common stock, net	3	3
Stock-based compensation expense	44,701		44,701
Ending balance at Dec. 31, 2022	$ (294,597)	$ 1,879	$ 1,158,118	$ 26	$ (1,454,620)