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Fair Value Measurements - Narrative (Details)	3 Months Ended		6 Months Ended		12 Months Ended
Fair Value Measurements - Narrative (Details)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
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Contingent consideration obligations	$ 273,500,000		273,500,000		$ 246,400,000
Contingent consideration related to the acquisition of Apellis	4,100,000	$ 0	4,100,000	$ 0
Apellis Pharmaceuticals, Inc.
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Debt Instrument [Line Items]
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