Employee Benefits - Defined Benefits (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Retirement Benefits [Abstract]
Plan assets	$ 133	$ 147
Benefit obligation	144	165
Unfunded status	$ 11	$ 18

No definition available.

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- Definition

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

+ References

+ Details

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- Definition

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.

+ References

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- Definition

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.

+ References

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