Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income Statement [Abstract]
Collaboration revenue	$ 14,030	$ 6,550	$ 25,282	$ 12,995
Type of Revenue [Extensible List]	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Operating expenses:
Research and development	$ 90,199	$ 58,884	$ 223,294	$ 98,160
General and administrative	22,132	16,683	44,535	30,277
Total operating expenses	112,331	75,567	267,829	128,437
Operating loss	(98,301)	(69,017)	(242,547)	(115,442)
Other (expense) income, net:
Interest income	703	211	1,243	431
Loss from equity method investment	(3,252)	0	(5,997)	0
Change in fair value of contingent consideration	172	0	(249)	0
Total other (expense) income, net	(2,377)	211	(5,003)	431
Net loss	$ (100,678)	$ (68,806)	$ (247,550)	$ (115,011)
Net Loss Per Share, Basic	$ (1.33)	$ (1.01)	$ (3.29)	$ (1.70)
Net Loss Per Share, Diluted	$ (1.33)	$ (1.01)	$ (3.29)	$ (1.70)
Weighted average shares outstanding, basic	75,823	68,164	75,282	67,675
Weighted average shares outstanding, diluted	75,823	68,164	75,282	67,675
Other comprehensive loss:
Unrealized loss on marketable securities	$ (932)	$ (1)	$ (6,060)	$ (14)
Other comprehensive loss from equity method investment	(560)	0	(862)	0
Comprehensive loss	$ (102,170)	$ (68,807)	$ (254,472)	$ (115,025)