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Intangible Assets and Goodwill - Summary of Intangible Assets (Details) - USD ($) $ in Millions | Sep. 30, 2024 | Dec. 31, 2023
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Finite-Lived Intangible Assets, Net [Abstract] |  |
Finite-Lived Intangible Assets, Gross | $ 14,101.5 | $ 11,728.8
Accumulated Amortization | (6,142.9) | (5,869.8)
Net | 7,958.6 | 5,859.0
Intangible Assets, Net (Excluding Goodwill) [Abstract] |  |
Cost | 15,948.4 | 14,232.8
Accumulated Amortization | 6,142.9 | 5,869.8
Net | 9,805.5 | 8,363.0
In-process research and development |  |
Indefinite-Lived Intangible Assets [Line Items] |  |
Cost and net | 1,682.9 | 2,340.0
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
Acquired and in-licensed rights and patents |  |
Finite-Lived Intangible Assets, Net [Abstract] |  |
Finite-Lived Intangible Assets, Gross | 10,552.9 | 8,180.2
Accumulated Amortization | (2,697.9) | (2,440.7)
Net | 7,855.0 | 5,739.5
Intangible Assets, Net (Excluding Goodwill) [Abstract] |  |
Accumulated Amortization | $ 2,697.9 | 2,440.7
Acquired and in-licensed rights and patents | Minimum |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated life (in years) | 2 years |
Acquired and in-licensed rights and patents | Maximum |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated life (in years) | 21 years |
Developed technology and other |  |
Finite-Lived Intangible Assets, Net [Abstract] |  |
Finite-Lived Intangible Assets, Gross | $ 3,548.6 | 3,548.6
Accumulated Amortization | (3,445.0) | (3,429.1)
Net | 103.6 | 119.5
Intangible Assets, Net (Excluding Goodwill) [Abstract] |  |
Accumulated Amortization | $ 3,445.0 | $ 3,429.1
Developed technology and other | Minimum |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated life (in years) | 13 years |
Developed technology and other | Maximum |  |
Finite-Lived Intangible Assets [Line Items] |  |
Estimated life (in years) | 31 years |

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