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Post-Employment and Other Long-Term Employees Benefits - Pension Plan Asset Allocation Including Fair-Value Measurements (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | $ 646 | $ 654 |
Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 7 | 7 |
Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 91 | 87 |
Government debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 63 | 69 |
Corporate debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 94 | 123 |
Investment funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 106 | 100 |
Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 10 | 9 |
Other (mainly insurance assets – contracts and reserves) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 275 | 259 |
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 24 | 22 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 7 | 7 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 1 | 1 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Government debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 0 | 0 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 0 | 0 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Investment funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 16 | 14 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 0 | 0 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Other (mainly insurance assets – contracts and reserves) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 0 | 0 |
Significant Other Observable Inputs (Level 2) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 390 | 399 |
Significant Other Observable Inputs (Level 2) | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 0 | 0 |
Significant Other Observable Inputs (Level 2) | Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 90 | 86 |
Significant Other Observable Inputs (Level 2) | Government debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 63 | 69 |
Significant Other Observable Inputs (Level 2) | Corporate debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 77 | 101 |
Significant Other Observable Inputs (Level 2) | Investment funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 90 | 86 |
Significant Other Observable Inputs (Level 2) | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 10 | 9 |
Significant Other Observable Inputs (Level 2) | Other (mainly insurance assets – contracts and reserves) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 60 | 48 |
Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 232 | 233 | $ 178
Significant Unobservable Inputs (Level 3) | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 0 | 0 |
Significant Unobservable Inputs (Level 3) | Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 0 | 0 |
Significant Unobservable Inputs (Level 3) | Government debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 0 | 0 |
Significant Unobservable Inputs (Level 3) | Corporate debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 17 | 22 |
Significant Unobservable Inputs (Level 3) | Investment funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 0 | 0 |
Significant Unobservable Inputs (Level 3) | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 0 | 0 |
Significant Unobservable Inputs (Level 3) | Other (mainly insurance assets – contracts and reserves) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | $ 215 | $ 211 |

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