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Intangible Assets and Goodwill - Summary of Intangible Assets (Details) - USD ($) $ in Millions | Mar. 31, 2024 | Dec. 31, 2023
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Finite-Lived Intangible Assets, Net [Abstract] |  |
Finite-Lived Intangible Assets, Gross | $ 14,028.8 | $ 11,728.8
Accumulated Amortization | (5,948.1) | (5,869.8)
Net | 8,080.7 | 5,859.0
Intangible Assets, Net (Excluding Goodwill) [Abstract] |  |
Cost | 14,232.8 | 14,232.8
Accumulated Amortization | 5,948.1 | 5,869.8
Net | 8,284.7 | 8,363.0
In-process research and development |  |
Indefinite-Lived Intangible Assets [Line Items] |  |
Cost and net | 40.0 | 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 | 10,480.2 | 8,180.2
Accumulated Amortization | (2,514.0) | (2,440.7)
Net | 7,966.2 | 5,739.5
Intangible Assets, Net (Excluding Goodwill) [Abstract] |  |
Accumulated Amortization | $ 2,514.0 | 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) | 22 years |
Developed technology and other |  |
Finite-Lived Intangible Assets, Net [Abstract] |  |
Finite-Lived Intangible Assets, Gross | $ 3,548.6 | 3,548.6
Accumulated Amortization | (3,434.1) | (3,429.1)
Net | 114.5 | 119.5
Intangible Assets, Net (Excluding Goodwill) [Abstract] |  |
Accumulated Amortization | $ 3,434.1 | $ 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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