Collaborations - Summary of Company's Collaboration Arrangements Earned in Period to Be Billed and Collected in Next Period (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Operating expenses:
Research and development	$ 31,096	$ 24,612	$ 58,071	$ 45,418
General and administrative	12,695	10,569	24,448	19,902
Total operating expenses	43,791	35,181	82,519	65,320
Incyte
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payments	(4,230)	(4,791)	(8,632)	(9,525)
Reimbursement revenue	2,250	2,470	4,214	4,487
Milestones	1,000		1,000
Other	0		0
Total collaboration revenue	7,480	7,261	13,846	14,012
Operating expenses:
Research and development	182	289	550	648
General and administrative	0		0
Total operating expenses	182	289	550	648
Revenue recognized in the period	4,230	4,791	8,632	9,525
Lilly
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payments	(4,147)	(3,765)	(8,185)	(4,911)
Reimbursement revenue	1,057	869	2,036	1,132
Milestones	0		0
Other	0		0
Total collaboration revenue	5,204	4,634	10,221	6,043
Operating expenses:
Research and development	0	0	0
General and administrative	0		0
Total operating expenses	0		0
Revenue recognized in the period	4,147	3,765	8,185
Other
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payments	(0)	(162)	(222)	(352)
Reimbursement revenue	0	322	0	322
Milestones	0		0
Other	0		50
Total collaboration revenue	0	484	272	674
Operating expenses:
Research and development	0	0	0
General and administrative	0		0
Total operating expenses	0		0
Revenue recognized in the period	0	162	222	352
Collaboration Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payments	(8,377)	(3,927)	(17,039)	(5,263)
Reimbursement revenue	3,307	1,191	6,250	1,454
Milestones	1,000		1,000
Other	0		50
Total collaboration revenue	12,684	5,118	24,339	6,717
Operating expenses:
Research and development	182	0	550
General and administrative	0		0
Total operating expenses	182		550
Revenue recognized in the period	$ 8,377	$ 3,927	$ 17,039	$ 352