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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	$ 1,053	$ 922	$ 2,977	$ 2,605
Retail \| Residential
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	486	442	1,453	1,265
Retail \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	555	469	1,487	1,305
Retail \| Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	12	11	37	35
Wholesale Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	60	61	195	150
Transmission Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	23	18	59	45
Other
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	53	38	159	120
Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,189	1,039	3,390	2,920
Alternative and Other [Member]
Disaggregation of Revenue [Line Items]
Alternative revenue and other	48	42	182	129
Regulated Electric \| Retail
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	908	786	2,203	1,995
Regulated Electric \| Retail \| Residential
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	386	344	904	825
Regulated Electric \| Retail \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	510	431	1,262	1,135
Regulated Electric \| Retail \| Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	12	11	37	35
Regulated Electric \| Wholesale Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	60	61	195	150
Regulated Electric \| Transmission Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	23	18	59	45
Regulated Electric \| Other
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	15	14	37	43
Regulated Electric \| Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,006	879	2,494	2,233
Regulated Electric \| Alternative and Other [Member]
Disaggregation of Revenue [Line Items]
Alternative revenue and other	42	37	114	110
Regulated Natural Gas \| Retail
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	135	128	743	581
Regulated Natural Gas \| Retail \| Residential
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	97	95	540	431
Regulated Natural Gas \| Retail \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	38	33	203	150
Regulated Natural Gas \| Retail \| Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
Regulated Natural Gas \| Wholesale Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
Regulated Natural Gas \| Transmission Services [Member]
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	38	24	122	77
Regulated Natural Gas \| Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	173	152	865	658
Regulated Natural Gas \| Alternative and Other [Member]
Disaggregation of Revenue [Line Items]
Alternative revenue and other	4	4	65	16
All Other \| Retail
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	10	8	31	29
All Other \| Retail \| Residential
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	3	3	9	9
All Other \| Retail \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	7	5	22	20
All Other \| Retail \| Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
All Other \| Wholesale Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	0	0	0	0
All Other \| Transmission Services [Member]
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	10	8	31	29
All Other \| Alternative and Other [Member]
Disaggregation of Revenue [Line Items]
Alternative revenue and other	2	1	3	3
Total revenues
Disaggregation of Revenue [Line Items]
Total revenues	1,237	1,081	3,572	3,049
Total revenues \| Regulated Electric
Disaggregation of Revenue [Line Items]
Total revenues	1,048	916	2,608	2,343
Total revenues \| Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Total revenues	177	156	930	674
Total revenues \| All Other
Disaggregation of Revenue [Line Items]
Total revenues	$ 12	$ 9	$ 34	$ 32