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Restructuring, Business Transformation and Other Cost Saving Initiatives - Narrative (Details) $ in Millions |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Sep. 26, 2023 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) Employee | Sep. 30, 2023 USD ($) | Jul. 31, 2023 USD ($)
Human Immunology Biosciences |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Integration related costs |  | $ 1.5 |  | $ 1.5 |  |
Minimum |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and Related Cost, Expected Cost Remaining |  |  |  |  |  | $ 260.0
Maximum |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring and Related Cost, Expected Cost Remaining |  |  |  |  |  | $ 280.0
2023 Cost Saving Initiatives |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Expected operating expense reduction | $ 1,000.0 |  |  |  |  |
Expected number of positions eliminated | Employee |  |  |  | 1,000 |  |
Severance Costs |  | 4.6 | $ 37.7 | $ 20.2 | $ 62.6 |
2023 Cost Saving Initiatives | Restructuring charges |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Severance Costs |  | 4.6 | 37.7 | 20.2 | 62.6 |
Reata Integration |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Severance Costs |  | 0.7 | 21.0 | 3.2 | 21.0 |
Reata Integration | Minimum |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Expected cost |  | 35.0 |  | 35.0 |  |
Reata Integration | Maximum |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Expected cost |  | 40.0 |  | 40.0 |  |
Reata Integration | Restructuring charges |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Severance Costs |  | $ 0.7 | $ 21.0 | $ 3.2 | $ 21.0 |

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