Employee Benefits - Plans ABO in Excess of Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
ABO	$ 1,200	$ 1,200
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
PBO	1,054	1,029
ABO	1,054	1,029
Fair value of plan assets	1,102	1,046
Other Defined Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
PBO	179	172
ABO	179	172
Fair value of plan assets	$ 0	$ 0

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Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

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-Publisher FASB
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Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

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