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Share-Based Payments - Share-Based Compensation Expense by Share-Based Compensation Program (Details) - USD ($) $ in Millions |  | 3 Months Ended
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Jul. 02, 2024 | Mar. 31, 2025 | Mar. 31, 2024
Summary of share based compensation expense associated with different programs [Abstract] |  |  |
Subtotal |  | $ 84.1 | $ 71.4
Capitalized share-based compensation costs |  | (3.1) | (3.3)
Share-based compensation expense included in total costs and expenses |  | 81.0 | 68.1
Human Immunology Biosciences |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |
Share-based compensation expense | $ 56.4 |  |
Market stock units |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |
Share-based compensation expense |  | 0.0 | 0.3
Time-vested restricted stock units |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |
Share-based compensation expense |  | 66.1 | 57.3
Performance stock units settled in stock |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |
Share-based compensation expense |  | 13.6 | 10.5
Performance stock units settled in cash |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |
Share-based compensation expense |  | 0.0 | (2.1)
Employee stock purchase plan |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |
Share-based compensation expense |  | 3.5 | 4.5
Options |  |  |
Summary of share based compensation expense associated with different programs [Abstract] |  |  |
Share-based compensation expense |  | $ 0.9 | $ 0.9

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