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No definition available.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Amount of revenue that is not accounted for under Topic 606.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Revenues (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Revenues (Details) - USD ($) $ in Millions	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 2,778	$ 2,534	$ 7,637	$ 6,942
Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	288	227	1,265	553
Transmission
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	167	157	461	442
Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	62	45	157	141
Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,295	2,963	9,520	8,078
Alternative revenue and other
Disaggregation of Revenue [Line Items]
Alternative revenue and other	172	219	556	501
Residential \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,144	1,097	3,295	3,035
C&I \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,598	1,401	4,241	3,809
Other \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	36	36	101	98
Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	3,467	3,182	10,076	8,579
Regulated Electric \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,549	2,336	6,414	5,931
Regulated Electric \| Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	288	227	1,265	553
Regulated Electric \| Transmission
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	167	157	461	442
Regulated Electric \| Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	17	17	51	55
Regulated Electric \| Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,021	2,737	8,191	6,981
Regulated Electric \| Alternative revenue and other
Disaggregation of Revenue [Line Items]
Alternative revenue and other	155	204	452	449
Regulated Electric \| Residential \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	999	962	2,488	2,356
Regulated Electric \| C&I \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,515	1,340	3,830	3,481
Regulated Electric \| Other \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	35	34	96	94
Regulated Electric \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	3,176	2,941	8,643	7,430
Regulated Natural Gas \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	209	180	1,163	955
Regulated Natural Gas \| Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Regulated Natural Gas \| Transmission
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Regulated Natural Gas \| Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	45	28	106	86
Regulated Natural Gas \| Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	254	208	1,269	1,041
Regulated Natural Gas \| Alternative revenue and other
Disaggregation of Revenue [Line Items]
Alternative revenue and other	14	11	95	41
Regulated Natural Gas \| Residential \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	133	124	774	647
Regulated Natural Gas \| C&I \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	76	56	389	308
Regulated Natural Gas \| Other \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Regulated Natural Gas \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	268	219	1,364	1,082
All Other \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	20	18	60	56
All Other \| Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
All Other \| Transmission
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
All Other \| Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
All Other \| Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	20	18	60	56
All Other \| Alternative revenue and other
Disaggregation of Revenue [Line Items]
Alternative revenue and other	3	4	9	11
All Other \| Residential \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	12	11	33	32
All Other \| C&I \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7	5	22	20
All Other \| Other \| Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1	2	5	4
All Other \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	$ 23	$ 22	$ 69	$ 67