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Share-Based Payments - Share-Based Compensation Expense by Share-Based Compensation Program (Details) - USD ($) $ in Millions |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Jul. 02, 2024 | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |  |
Share-based compensation expense |  | $ (75.0) | $ (64.8) | $ (224.0) | $ (217.8)
Subtotal |  | 131.1 | 452.0 | 275.4 | 609.7
Capitalized share-based compensation costs |  | (2.4) | (2.6) | (8.0) | (8.5)
Share-based compensation expense included in total costs and expenses |  | 128.7 | 449.4 | 267.4 | 601.2
Reata Pharmaceuticals, Inc |  |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |  |
Share-based compensation expense |  | 0.0 | 387.0 | 0.0 | 387.0
Human Immunology Biosciences |  |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |  |
Share-based compensation expense | $ 56.4 | 56.4 | 0.0 | 56.4 | 0.0
Market stock units |  |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |  |
Share-based compensation expense |  | 0.2 | 0.7 | 0.6 | 4.2
Time-vested restricted stock units |  |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |  |
Share-based compensation expense |  | 59.1 | 53.4 | 174.7 | 175.0
Performance stock units settled in stock |  |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |  |
Share-based compensation expense |  | 13.0 | 7.8 | 35.2 | 27.1
Performance stock units settled in cash |  |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |  |
Share-based compensation expense |  | (0.5) | 0.1 | (2.5) | 4.8
Employee stock purchase plan |  |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |  |
Share-based compensation expense |  | 1.9 | 2.0 | 8.2 | 8.8
Options |  |  |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |  |  |
Share-based compensation expense |  | $ 1.0 | $ 1.0 | $ 2.8 | $ 2.8

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