Revenue from Contracts with Customers - PAC (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Disaggregation of Revenue [Line Items]
Operating revenue	$ 7,500	$ 6,968	$ 20,142	$ 19,113
Regulated
Disaggregation of Revenue [Line Items]
Total Customer Revenue	5,055	4,430	13,159	12,111
Regulated | Retail electric
Disaggregation of Revenue [Line Items]
Total Customer Revenue	3,513	3,096	8,360	7,615
Regulated | Wholesale
Disaggregation of Revenue [Line Items]
Total Customer Revenue	310	203	733	504
Regulated | Transmission and distribution
Disaggregation of Revenue [Line Items]
Total Customer Revenue	522	521	1,553	1,512
Regulated | Other
Disaggregation of Revenue [Line Items]
Total Customer Revenue	24	24	74	80
PAC
Disaggregation of Revenue [Line Items]
Other revenue	23	0	47	25
Operating revenue	1,635	1,491	4,246	4,031
PAC | Regulated
Disaggregation of Revenue [Line Items]
Total Customer Revenue	1,612	1,491	4,199	4,006
PAC | Regulated | Retail electric
Disaggregation of Revenue [Line Items]
Total Customer Revenue	1,465	1,352	3,817	3,685
PAC | Regulated | Wholesale
Disaggregation of Revenue [Line Items]
Total Customer Revenue	69	58	179	124
PAC | Regulated | Transmission and distribution
Disaggregation of Revenue [Line Items]
Total Customer Revenue	54	55	131	117
PAC | Regulated | Other
Disaggregation of Revenue [Line Items]
Total Customer Revenue	24	26	72	80
PAC | Regulated | Residential | Retail electric
Disaggregation of Revenue [Line Items]
Total Customer Revenue	576	530	1,498	1,442
PAC | Regulated | Commercial | Retail electric
Disaggregation of Revenue [Line Items]
Total Customer Revenue	461	428	1,224	1,180
PAC | Regulated | Industrial | Retail electric
Disaggregation of Revenue [Line Items]
Total Customer Revenue	310	296	860	849
PAC | Regulated | Other retail | Retail electric
Disaggregation of Revenue [Line Items]
Total Customer Revenue	$ 118	$ 98	$ 235	$ 214