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Segment Reporting - Schedule of Equity Income from Affiliates and Depreciation Included in Segment Profits (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Segment Reporting Information [Line Items] |  |  |  |
Depreciation |  |  | $ 1,552 | $ 1,582
Operating Segments |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Equity income from affiliates | $ 62 | $ 43 | 148 | 121
Depreciation | 83 | 86 | 207 | 214
Operating Segments | Pharma- ceutical |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Equity income from affiliates | 62 | 43 | 148 | 121
Depreciation | 1 | 1 | 4 | 3
Operating Segments | Animal Health |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Equity income from affiliates | 0 | 0 | 0 | 0
Depreciation | $ 82 | $ 85 | $ 203 | $ 211

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