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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, 2022 | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 565 | $ 743 |
Cash and Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 4 | 5 |
Equity Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 95 | 130 |
Government Debt Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 59 | 87 |
Corporate Debt Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 120 | 164 |
Investment Funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 87 | 156 |
Real Estate [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 6 | 10 |
Other (Mainly Insurance Assets - Contracts and Reserves) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 194 | 191 |
Fair Value, Inputs, Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 6 | 8 |
Fair Value, Inputs, Level 1 [Member] | Cash and Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 4 | 5 |
Fair Value, Inputs, Level 1 [Member] | Equity Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 1 | 2 |
Fair Value, Inputs, Level 1 [Member] | Investment Funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 1 | 1 |
Fair Value, Inputs, Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 381 | 568 |
Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 94 | 128 |
Fair Value, Inputs, Level 2 [Member] | Government Debt Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 59 | 87 |
Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 98 | 139 |
Fair Value, Inputs, Level 2 [Member] | Investment Funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 86 | 155 |
Fair Value, Inputs, Level 2 [Member] | Real Estate [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 6 | 10 |
Fair Value, Inputs, Level 2 [Member] | Other (Mainly Insurance Assets - Contracts and Reserves) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 38 | 49 |
Fair Value, Inputs, Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 178 | 167 | $ 162
Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 22 | 25 |
Fair Value, Inputs, Level 3 [Member] | Other (Mainly Insurance Assets - Contracts and Reserves) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 156 | $ 142 |

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