Employee Retirement Benefits (Reconciliation Of The Funded Status For Qualified Plan And SERP) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Retirement Benefits [Abstract]
Assets for Plan Benefits, Defined Benefit Plan	$ 4	$ 0
Total	4	0
Pension amounts recognized in accumulated other comprehensive income:
Net actuarial loss	9	16
Total	$ 9	$ 16

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Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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