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Post-Employment and Other Long-Term Employees Benefits - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expected amortization of actuarial losses in year 2016 | $ 9 |  |
Pension plans with accumulated benefit obligations in excess of plan assets, accumulated benefit obligation | 738 | $ 547 |
Pension plans with accumulated benefit obligations in excess of plan assets, fair value of plan assets | 443 | 284 |
Accrued benefits related to defined contribution pension plans | 16 | 16 |
Annual cost of defined contribution plans | 70 | 70 | $ 81
Pension Benefits [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension plans with benefit obligations in excess of plan assets, benefit obligation | 811 | 653 |
Pension plans with benefit obligations in excess of plan assets, fair value of plan assets | 464 | 302 |
Employer contributions | 27 | $ 28 |
Expected contribution in cash | $ 28 |  |

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