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Post-Employment and Other Long-Term Employees Benefits - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension plans with accumulated benefit obligations in excess of plan assets, accumulated benefit obligation | $ 773 | $ 952 |
Pension plans with accumulated benefit obligations in excess of plan assets, fair value of plan assets | 327 | 562 |
Pension plans with accumulated benefit obligations in excess of plan assets, projected benefit obligation | 675 | 562 |
Pension benefits components other than service cost, | 12 | 16 | $ 11
Accrued benefits related to defined contribution pension plans | 23 | 20 |
Annual cost of defined contribution plans | 91 | 86 | $ 84
Pension Benefits [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension plans with benefit obligations in excess of plan assets, benefit obligation | 1,177 | 1,005 |
Employer contributions | 17 | $ 21 |
Expected contribution in cash | $ 22 |  |

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