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Post-Employment and Other Long-Term Employees Benefits - Pension Plan Asset Allocation Including Fair-Value Measurements (Detail) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | $ 654 | $ 565 |
Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 7 | 4 |
Equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 87 | 95 |
Government debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 69 | 59 |
Corporate debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 123 | 120 |
Investment in funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 100 | 87 |
Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 9 | 6 |
Other (mainly insurance assets – contracts and reserves) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 259 | 194 |
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 22 | 6 |
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 | 4 |
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 in funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 14 | 1 |
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 | 399 | 381 |
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 | 86 | 94 |
Significant Other Observable Inputs (Level 2) | Government debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 69 | 59 |
Significant Other Observable Inputs (Level 2) | Corporate debt securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 101 | 98 |
Significant Other Observable Inputs (Level 2) | Investment in funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 86 | 86 |
Significant Other Observable Inputs (Level 2) | Real estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 9 | 6 |
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 | 48 | 38 |
Significant Unobservable Inputs (Level 3) |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | 233 | 178 | $ 167
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 | 22 | 22 |
Significant Unobservable Inputs (Level 3) | Investment in 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 | $ 211 | $ 156 |

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