License, Acquisitions and Other Agreements - Taldefgrobep Alfa License Agreement (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
License and other agreements
Milestone payment to be paid upon regulatory achievement	$ 701,975,000		$ 701,975,000
Research and development	184,367,000	$ 314,819,000	371,951,000	$ 470,791,000
BMS
License and other agreements
Research and development	0	$ 0	0	$ 0
BMS | Taldefgrobep Alfa License Agreement
License and other agreements
Milestone payment to be paid upon regulatory achievement	$ 200,000,000		$ 200,000,000