Regulatory Matters (Components Of Regulatory Assets And Liabilities) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	$ 1,646	$ 1,547
Carrying Amount, Regulatory Liabilities	3,000	2,876
Net regulatory assets (liabilities)	(1,354)	(1,329)
Estimated Net Removal Costs [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Liabilities	1,412	1,348
Excess Deferred Taxes [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Liabilities	1,392	1,442
Over-Recovered Wholesale Transmission Service Expense [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Liabilities	85	7
Unamortized Gain On Reacquisition Of Debt [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Liabilities	25	26
Employee Retirement Costs Over Recovered Since Last Rate Review Period [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Liabilities	55	39
Other Regulatory Liabilities [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Liabilities	31	14
Employee Retirement Liability [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	$ 309	328
Employee Retirement Costs Being Amortized [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	5 years
Carrying Amount, Regulatory Assets	$ 166	193
Employee Retirement Costs Incurred Since The Last Rate Review Period [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	$ 93	99
Self-Insurance Reserve (Primarily Storm Recovery Costs) Being Amortized [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	5 years
Carrying Amount, Regulatory Assets	$ 191	223
Self-Insurance Reserve Incurred Since The Last Rate Review Period (Primarily Storm Related) [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	542	373
Debt Reacquisition Costs [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	$ 16	19
Under-recovered AMS Costs [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	5 years
Carrying Amount, Regulatory Assets	$ 112	128
Energy Efficiency Performance Bonus [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	36	31
Wholesale Distribution Substation Service [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	89	75
Unrecovered Expenses Related To Covid19 [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	37	35
Recoverable Deferred Income Taxes Net [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	22	16
Uncollectible Payments From Reps [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	8	9
Other Regulatory Assets [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	$ 25	$ 18
Maximum [Member] | Over-Recovered Wholesale Transmission Service Expense [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	1 year
Maximum [Member] | Energy Efficiency Performance Bonus [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	1 year