Employee Retirement Benefits (Reconciliation Of The Funded Status For Qualified Plan And SERP) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Retirement Benefits [Abstract]
Other assets		$ 4
Other liabilities	$ (30)
Total	(30)	4
Pension amounts recognized in accumulated other comprehensive income:
Net actuarial loss	41	9
Total	$ 41	$ 9

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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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