Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement [Abstract]
Collaboration revenue	$ 6,957	$ 13,594	$ 35,892	$ 26,200
Type of Revenue [Extensible List]	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Operating expenses:
Research and development	$ 114,207	$ 115,276	$ 226,054	$ 212,392
General and administrative	31,793	30,652	62,884	58,100
Total operating expenses	146,000	145,928	288,938	270,492
Operating loss	(139,043)	(132,334)	(253,046)	(244,292)
Other (expense) income, net:
Interest income	12,422	12,653	25,054	24,633
Change in fair value of investments, net	(20,354)	0	(26,419)	0
Loss from equity method investment	0	(4,000)	0	(7,048)
Change in fair value of contingent consideration	0	0	0	(100)
Total other (expense) income , net	(7,932)	8,653	(1,365)	17,485
Net loss	$ (146,975)	$ (123,681)	$ (254,411)	$ (226,807)
Net loss per share, basic	$ (1.52)	$ (1.4)	$ (2.64)	$ (2.58)
Net loss per share, diluted	$ (1.52)	$ (1.4)	$ (2.64)	$ (2.58)
Weighted average shares outstanding, basic	96,975	88,185	96,238	87,979
Weighted average shares outstanding, diluted	96,975	88,185	96,238	87,979
Other comprehensive (loss) gain:
Unrealized (loss) gain on marketable securities	$ (208)	$ (1,482)	$ (1,029)	$ 1,507
Other comprehensive gain - equity method investment	0	292	0	2,086
Comprehensive loss	$ (147,183)	$ (124,871)	$ (255,440)	$ (223,214)