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Collaboration and Licensing Agreements - Narrative (Details) $ in Thousands					1 Months Ended					3 Months Ended			6 Months Ended		12 Months Ended		36 Months Ended
	Jan. 01, 2029 USD ($)	Jul. 30, 2026 USD ($)	Dec. 29, 2025 USD ($)	Jul. 01, 2023 USD ($)	Aug. 05, 2026 USD ($)	Jun. 30, 2025 USD ($)	Mar. 31, 2025 USD ($)	Feb. 28, 2025 USD ($)	Jan. 31, 2013 program	Jun. 30, 2026 USD ($)	Mar. 31, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2019 USD ($) target	Dec. 31, 2028 USD ($)	May 31, 2026 USD ($) Contract
Collaboration research and licensing agreements
Increase (decrease) in accounts receivable													$ 22,636	$ (14,636)
Accounts receivable										$ 42,234			42,234		$ 29,299
Alexion \| Option and License Agreement
Collaboration research and licensing agreements
Number of different target programs \| program									1
Accounts receivable										37,800			37,800
Alexion \| Option and License Agreement \| OCM Life Sciences Portfolio LP
Collaboration research and licensing agreements
Accounts receivable										12,600			12,600
Alexion \| Option and License Agreement \| Royalties
Collaboration research and licensing agreements
Increase (decrease) in royalty revenue											$ (6,600)
Increase (decrease) in accounts receivable											$ (6,600)
Revenue recognized										37,300		$ 16,800	38,800	32,300
Alexion \| Option and License Agreement \| Royalties \| Forecast
Collaboration research and licensing agreements
Expected royalty interest payments	$ 12,000																$ 35,000
Alexion \| Ultomiris Royalty Sale Agreement \| Royalties
Collaboration research and licensing agreements
Revenue recognized										27,600			27,600
Alexion \| Ultomiris Royalty Sale Agreement \| Royalties \| Forecast
Collaboration research and licensing agreements
Revenue recognized					$ 77,400
MorphoSys \| Collaboration and License Agreement
Collaboration research and licensing agreements
Proceeds from milestone payment received			$ 4,000			$ 25,000		$ 12,500
Royalty milestones										195,000			195,000
MorphoSys \| Collaboration and License Agreement \| Royalties
Collaboration research and licensing agreements
Revenue recognized										3,900			6,800
Accounts receivable										4,400			4,400
Expected royalty interest payments				$ 29,300
Royalties received										29,300
MorphoSys \| Collaboration and License Agreement \| Non-Cash Royalty
Collaboration research and licensing agreements
Revenue recognized										3,100		1,800		4,500
MorphoSys \| Collaboration and License Agreement \| Royalty Payable to Company
Collaboration research and licensing agreements
Revenue recognized										800
OCM Life Sciences Portfolio LP (OMERS) \| Collaboration and License Agreement \| Royalties
Collaboration research and licensing agreements
Accounts receivable										3,600			3,600
OCM Life Sciences Portfolio LP (OMERS) \| Monjuvi Royalty Sale Agreement
Collaboration research and licensing agreements
Proceeds from milestone payment received															$ 41,500
Vir Bio \| Patent License Agreement
Collaboration research and licensing agreements
Number of different target programs \| target																2
Revenue recognized							$ 2,000
Royalty milestones																$ 65,000
Vir Bio \| Patent License Agreement \| Royalties
Collaboration research and licensing agreements
Revenue recognized										$ 0		$ 0	$ 0	$ 0
Zenas Bio Pharma Limited \| License Agreement \| Potential Milestones Type
Collaboration research and licensing agreements
Royalty milestones																		$ 450,000
Equity shares estimated fair value																		$ 10,000
Number of collaborative arrangements \| Contract																		2
Zenas Bio Pharma Limited \| License Agreement \| Potential Milestones Type \| Forecast
Collaboration research and licensing agreements
Revenue recognized		$ 2,500