Revenue Recogniton Revenue Recognition Disaggregation of Revenue (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Document Period End Date	Dec. 31, 2023
Regulated Operating Revenue, Electric, Non-Nuclear	$ 2,439	$ 2,205	$ 2,105
Contract with Customer, Liability, Cumulative Catch-up Adjustment to Revenue, Change in Estimate of Transaction Price	11	11	(29)
Deferred Revenue, Revenue Recognized	(3)	(7)	(2)
Regulated Operating Revenue	2,447	2,223	2,078
Unregulated Operating Revenue	418	363	255
Regulated and Unregulated Operating Revenue	58	61	63
Total Revenues	2,923	2,647	2,396
Gain on Derivative Instruments, Pretax	185	133	63
Residential [Member]
Disaggregation of Revenue [Line Items]
Regulated Operating Revenue, Electric, Non-Nuclear	1,263	1,158	1,118
Commercial [Member]
Disaggregation of Revenue [Line Items]
Regulated Operating Revenue, Electric, Non-Nuclear	800	723	690
Industrial [Member]
Disaggregation of Revenue [Line Items]
Regulated Operating Revenue, Electric, Non-Nuclear	349	289	250
Direct Access customers [Member]
Disaggregation of Revenue [Line Items]
Regulated Operating Revenue, Electric, Non-Nuclear	$ 27	$ 35	$ 47