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Acquisitions - Purchase Price Consideration (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions |  |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | ---
Jul. 02, 2024 | Sep. 26, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Business Acquisition [Line Items] |  |  |  |  |  |
Share-based Payment Arrangement, Expense |  |  | $ (75.0) | $ (64.8) | $ (224.0) | $ (217.8)
Human Immunology Biosciences |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Total transaction value | $ 1,137.3 |  |  |  |  |
Contingent consideration | 485.1 |  |  |  |  |
Consideration transferred | 1,622.4 |  |  |  |  |
Working capital adjustment | 43.7 |  |  |  |  |
Share-based Payment Arrangement, Expense | 56.4 |  | 56.4 | 0.0 | 56.4 | 0.0
Human Immunology Biosciences | Previously Reported |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Total transaction value | $ 1,150.0 |  |  |  |  |
Reata Pharmaceuticals, Inc |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Total transaction value |  | $ 6,602.9 |  |  |  |
Consideration transferred |  | $ 7,193.4 |  |  |  |
Share-based Payment Arrangement, Expense |  |  | $ 0.0 | $ 387.0 | $ 0.0 | $ 387.0
Price per share (in dollars per share) |  | $ 172.50 |  |  |  |
Number of common stock shares acquired |  | 38.3 |  |  |  |

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