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Fair Value Measurements - Narrative (Details)	3 Months Ended	9 Months Ended
Fair Value Measurements - Narrative (Details)	Sep. 30, 2025 USD ($)	Sep. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)	Jul. 02, 2024 USD ($)
Debt Instrument [Line Items]
Asset impairment charges	$ 0	$ 0
Contingent consideration obligations	148,600,000	148,600,000	$ 291,200,000
Contingent consideration obligations	$ 242,600,000	$ 242,600,000	$ 221,600,000
Human Immunology Biosciences
Debt Instrument [Line Items]
Contingent consideration obligations				$ 279,300,000
Contingent consideration obligations				205,800,000
Human Immunology Biosciences \| Maximum \| Phase 3 Clinical Trial, Felzartamab One
Debt Instrument [Line Items]
Contingent consideration obligations				150,000,000
Human Immunology Biosciences \| Maximum \| Phase 3 Clinical Trial, Felzartamab Two
Debt Instrument [Line Items]
Contingent consideration obligations				$ 150,000,000
Human Immunology Biosciences \| Measurement Input, Probability Rate
Debt Instrument [Line Items]
Discount rate	0.700	0.700		0.670