Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
Collaboration revenue	$ 36,275	$ 52,121	$ 33,053
Type of Revenue [Extensible List]	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Operating expenses:
Research and development	$ 435,069	$ 419,979	$ 229,807
General and administrative	116,497	90,306	71,096
Total operating expenses	551,566	510,285	300,903
Operating loss	(515,291)	(458,164)	(267,850)
Other income (expense), net:
Interest income	49,832	8,542	1,283
Loss from equity method investments	(15,633)	(11,079)	(1,325)
Change in fair value of contingent consideration	(100)	(13,485)	0
Total other income (expense), net	34,099	(16,022)	(42)
Net loss	$ (481,192)	$ (474,186)	$ (267,892)
Net Loss Per Share, Basic	$ (5.42)	$ (6.16)	$ (3.78)
Net Loss Per Share, Diluted	$ (5.42)	$ (6.16)	$ (3.78)
Weighted average shares outstanding, basic	88,770	76,972	70,894
Weighted average shares outstanding, diluted	88,770	76,972	70,894
Other comprehensive loss:
Unrealized gain (loss) on marketable securities	$ 3,635	$ (1,637)	$ (2,126)
Other comprehensive gain (loss) from equity method investment	1,568	(3,192)	(507)
Comprehensive loss	$ (475,989)	$ (479,015)	$ (270,525)