Employee Benefit Plans - Postemployment Plan (Details) - Postemployment Retirement Benefits [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Net service cost	$ 6	$ 14
Interest cost	0	1
Amortization of prior service benefit	0	(1)
Amortization of actuarial gain	(1)	(1)
Net benefit cost	$ 5	$ 13

Defined Benefit Plan Net Periodic Benefit Costs, Subtotal

No definition available.

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- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

+ References

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- Definition

Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

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- Definition

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

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- Details

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