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Intangible Assets and Goodwill - Summary of Intangible Assets (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
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Finite-Lived Intangible Assets, Net [Abstract] |  |
Finite-Lived Intangible Assets, Gross | $ 14,103.6 | $ 14,138.4
Accumulated Amortization | (6,325.9) | (6,254.1)
Net | 7,777.7 | 7,884.3
Intangible Assets, Net (Excluding Goodwill) [Abstract] |  |
Cost | 15,910.5 | 15,945.3
Accumulated Amortization | 6,325.9 | 6,254.1
Net | $ 9,584.6 | 9,691.2
Minimum |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated life (in years) | 2 years |
Maximum |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated life (in years) | 31 years |
In-process research and development |  |
Indefinite-Lived Intangible Assets [Line Items] |  |
Cost and net | $ 1,642.9 | 1,642.9
Priority review voucher |  |
Indefinite-Lived Intangible Assets [Line Items] |  |
Cost and net | 100.0 | 100.0
Trademarks and trade names |  |
Indefinite-Lived Intangible Assets [Line Items] |  |
Cost and net | $ 64.0 | $ 64.0

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