Collaboration and Licensing Agreements - Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Collaboration research and licensing agreements
Revenue recorded	$ 16,960	$ 45,523	$ 29,765	$ 64,485
Research collaboration
Collaboration research and licensing agreements
Revenue recorded	0	22,200	0	22,500
License
Collaboration research and licensing agreements
Revenue recorded	8,500	0	8,500	0
Milestone
Collaboration research and licensing agreements
Revenue recorded	0	10,000	500	15,000
Royalties
Collaboration research and licensing agreements
Revenue recorded	0	13,300	100	27,000
Non-cash royalties
Collaboration research and licensing agreements
Revenue recorded	8,500	0	20,700	0
Alexion
Collaboration research and licensing agreements
Revenue recorded	6,900	11,200	16,300	21,600
Janssen
Collaboration research and licensing agreements
Revenue recorded	0	22,200	0	27,500
Mabgeek
Collaboration research and licensing agreements
Revenue recorded	1,500	0	1,500	0
Mabgeek | Technology License Agreement
Collaboration research and licensing agreements
Revenue recorded	1,500		1,500
MorphoSys
Collaboration research and licensing agreements
Revenue recorded	1,600	2,000	4,400	3,900
Vega | Technology License Agreement
Collaboration research and licensing agreements
Revenue recorded	0	0	500	0
Vir
Collaboration research and licensing agreements
Revenue recorded	0	100	100	1,500
Viridian | Technology License Agreement
Collaboration research and licensing agreements
Revenue recorded	0	0	0	0
Zenas
Collaboration research and licensing agreements
Revenue recorded	0	10,000	0	10,000
Third Party Licensee
Collaboration research and licensing agreements
Revenue recorded	$ 7,000	$ 0	$ 7,000	$ 0