Pension, OPEB and Savings Plans (Reconciliations Of The Beginning And Ending Balances Of Pension And OPEB Plans' Level 3 Assets) (Details) $ in Millions	Dec. 31, 2023 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Assets at Beginning of Year	$ 5,331	[1]
Fair Value of Assets at End of Year	4,578	[1]
Private Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Assets at Beginning of Year	3
Fair Value of Assets at End of Year	$ 2

[1] Excludes net receivables of $2 million and $7 million as of December 31, 2023 and 2022, respectively, which consist of interest, dividends and receivables and payables related to pending securities sales and purchases. In addition, the table excludes cash and foreign currency of $2 million as of December 31, 2022.