Condensed Consolidated Statements of Stockholders' Deficit (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Private Placement	Common Stock	Common Stock Private Placement	Additional Paid-In Capital	Additional Paid-In Capital Private Placement	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Balance at Dec. 31, 2022	$ 13,572		$ 1,191		$ 1,807,855		$ (19)	$ (1,795,455)
Balance (in shares) at Dec. 31, 2022			119,155
Issuance of common stock under equity incentive plan	(208)		$ 2		(210)
Issuance of common stock under equity incentive plan (in shares)			125
Stock-based compensation expense	7,947				7,947
Net loss	(32,768)							(32,768)
Net unrealized gains (losses) on short-term investments	28						28
Comprehensive loss	(32,740)
Balance at Mar. 31, 2023	(11,429)		$ 1,193		1,815,592		9	(1,828,223)
Balance (in shares) at Mar. 31, 2023			119,280
Balance at Dec. 31, 2022	13,572		$ 1,191		1,807,855		(19)	(1,795,455)
Balance (in shares) at Dec. 31, 2022			119,155
Net loss	(99,835)
Net unrealized gains (losses) on short-term investments	18
Comprehensive loss	(99,817)
Balance at Sep. 30, 2023	(27,786)		$ 1,411		1,866,094		(1)	(1,895,290)
Balance (in shares) at Sep. 30, 2023			141,101
Balance at Mar. 31, 2023	(11,429)		$ 1,193		1,815,592		9	(1,828,223)
Balance (in shares) at Mar. 31, 2023			119,280
Issuance of common stock under equity incentive plan	(385)		$ 3		(388)
Issuance of common stock under equity incentive plan (in shares)			330
Issuance of common stock under the employee stock purchase plan	704		$ 3		701
Issuance of common stock under the employee stock purchase plan (in shares)			346
Stock-based compensation expense	13,900				13,900
Net loss	(42,059)							(42,059)
Net unrealized gains (losses) on short-term investments	(15)						(15)
Comprehensive loss	(42,074)
Balance at Jun. 30, 2023	(39,284)		$ 1,199		1,829,805		(6)	(1,870,282)
Balance (in shares) at Jun. 30, 2023			119,956
Issuance of common stock under equity incentive plan	(308)		$ 4		(312)
Issuance of common stock under equity incentive plan (in shares)			410
Issuance of common stock in a private placement, net		$ 29,755		$ 208		$ 29,547
Issuance of common stock in a private placement, net (in shares)				20,735
Issuance of warrants in debt financing	371				371
Stock-based compensation expense	6,683				6,683
Net loss	(25,008)							(25,008)
Net unrealized gains (losses) on short-term investments	5						5
Comprehensive loss	(25,003)
Balance at Sep. 30, 2023	(27,786)		$ 1,411		1,866,094		(1)	(1,895,290)
Balance (in shares) at Sep. 30, 2023			141,101
Balance at Dec. 31, 2023	(33,973)		$ 1,503		1,870,525		13	(1,906,014)
Balance (in shares) at Dec. 31, 2023			150,285
Issuance of common stock under equity incentive plan	11		$ 1		10
Issuance of common stock under equity incentive plan (in shares)			93
Stock-based compensation expense	3,375				3,375
Net loss	(3,160)							(3,160)
Net unrealized gains (losses) on short-term investments	(19)						(19)
Comprehensive loss	(3,179)
Balance at Mar. 31, 2024	(33,766)		$ 1,504		1,873,910		(6)	(1,909,174)
Balance (in shares) at Mar. 31, 2024			150,378
Balance at Dec. 31, 2023	(33,973)		$ 1,503		1,870,525		13	(1,906,014)
Balance (in shares) at Dec. 31, 2023			150,285
Net loss	(17,243)
Net unrealized gains (losses) on short-term investments	27
Comprehensive loss	(17,216)
Balance at Sep. 30, 2024	(40,005)		$ 1,517		1,881,695		40	(1,923,257)
Balance (in shares) at Sep. 30, 2024			151,702
Balance at Mar. 31, 2024	(33,766)		$ 1,504		1,873,910		(6)	(1,909,174)
Balance (in shares) at Mar. 31, 2024			150,378
Issuance of common stock under equity incentive plan	318		$ 9		309
Issuance of common stock under equity incentive plan (in shares)			872
Issuance of common stock under the employee stock purchase plan	175		$ 3		172
Issuance of common stock under the employee stock purchase plan (in shares)			328
Stock-based compensation expense	4,570				4,570
Net loss	(9,235)							(9,235)
Net unrealized gains (losses) on short-term investments	(2)						(2)
Comprehensive loss	(9,237)
Balance at Jun. 30, 2024	(37,940)		$ 1,516		1,878,961		(8)	(1,918,409)
Balance (in shares) at Jun. 30, 2024			151,578
Issuance of common stock under equity incentive plan	13		$ 1		12
Issuance of common stock under equity incentive plan (in shares)			124
Stock-based compensation expense	2,722				2,722
Net loss	(4,848)							(4,848)
Net unrealized gains (losses) on short-term investments	48						48
Comprehensive loss	(4,800)
Balance at Sep. 30, 2024	$ (40,005)		$ 1,517		$ 1,881,695		$ 40	$ (1,923,257)
Balance (in shares) at Sep. 30, 2024			151,702