Employee Benefit Plans - Change in Benefit Obligation, Plan Assets and Funded Status of Defined Benefit Pension Plans (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	$ 588
Fair value of plan assets at end of year	517	$ 588
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	633	622
Service cost	1	1
Interest cost	18	20
Actuarial loss (gain)	(24)	6
Benefits paid	(40)	(31)
Exchange rate loss (gain)	(15)	30
Plan amendments	4
Settlements	(2)	(15)
Benefit obligation at end of year	575	633
Fair value of plan assets at beginning of year	588	543
Actual return	(21)	57
Benefits paid	(40)	(31)
Company contributions	5	11
Exchange rate gain (loss)	(13)	24
Settlements	(2)	(15)
Other		(1)
Fair value of plan assets at end of year	517	588
Funded status	(58)	(45)
Accumulated benefit obligation at end of year	572	630
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	62	92
Interest cost	2	3
Actuarial loss (gain)	(8)	(17)
Benefits paid	(13)	(14)
Participants contributions	2	2
Curtailments		(4)
Benefit obligation at end of year	45	62
Benefits paid	(13)	(14)
Company contributions	11	12
Participants contributions	2	2
Funded status	$ (45)	$ (62)

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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Amount of contributions received by defined benefit plan from participant which increase benefit obligation.

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Amount of (increase) decrease in benefit obligation of defined benefit plan from event reducing expected years of future service of present employees or eliminating accrual of benefits for some or all future services of present employees.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of foreign currency translation gain (loss) which (increases) decreases benefit obligation of defined benefit plan.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of defined benefit plan cost (credit), classified as other.

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Amount of increase (decrease) in benefit obligation of defined benefit plan from change in terms of existing plan or initiation of new plan.

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Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement.

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