Fair Value Measurements - Contingent Consideration Obligations (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Business Combination, Contingent Consideration, Liability [Roll Forward] | ||||
| Fair value, beginning of period | $ 273.5 | $ 534.9 | $ 246.4 | $ 512.8 |
| Contingent consideration related to the acquisition of Apellis | 0.0 | 0.0 | 4.1 | 0.0 |
| (Gain) loss on fair value remeasurement of contingent consideration | 0.4 | 5.6 | 23.4 | 28.4 |
| Payments | 0.0 | (149.3) | 0.0 | (150.0) |
| Fair value, end of period | $ 273.9 | $ 391.2 | $ 273.9 | $ 391.2 |
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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