Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Income Statement [Abstract]
Collaboration revenue	$ 14,245	$ 6,957	$ 30,872	$ 35,892
Type of Revenue [Extensible List]	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Operating expenses:
Research and development	$ 97,035	$ 114,207	$ 205,462	$ 226,054
General and administrative	27,206	31,793	56,213	62,884
Total operating expenses	124,241	146,000	261,675	288,938
Operating loss	(109,996)	(139,043)	(230,803)	(253,046)
Other income (expense), net:
Interest income	7,402	12,422	16,005	25,054
Change in fair value of investments, net	1,339	(20,354)	(786)	(26,419)
Total other income (expense), net	8,741	(7,932)	15,219	(1,365)
Net loss	$ (101,255)	$ (146,975)	$ (215,584)	$ (254,411)
Net loss per share, basic	$ (0.98)	$ (1.52)	$ (2.08)	$ (2.64)
Net loss per share, diluted	$ (0.98)	$ (1.52)	$ (2.08)	$ (2.64)
Weighted average shares outstanding, basic	103,732	96,975	103,617	96,238
Weighted average shares outstanding, diluted	103,732	96,975	103,617	96,238
Other comprehensive loss:
Unrealized (loss) gain on marketable securities	$ (404)	$ (208)	$ 48	$ (1,029)
Comprehensive loss	$ (101,659)	$ (147,183)	$ (215,536)	$ (255,440)