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Employee Benefit Plans - Additional Information (Detail) $ in Millions | 12 Months Ended
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Dec. 31, 2018 USD ($) Employee | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Compensation Related Costs Disclosure [Line Items] |  |  |
Expenses for defined-contribution plans | $ 68 | $ 64 | $ 66
Net periodic benefit cost | (3) | $ 1 | $ 5
Defined benefit plan, expected future benefit payments in year five | $ 33 |  |
Expected years of defined benefit plans | 5 years |  |
Expected future benefit amounts to pay, total | $ 319 |  |
United States [Member] |  |  |
Compensation Related Costs Disclosure [Line Items] |  |  |
Number of U.S. employees participate in defined benefit health care plans | Employee | 43 |  |
Number of U.S retirees and spouses participate in defined benefit health care plans | Employee | 1,694 |  |

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