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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		6 Months Ended
Revenues (Details) - USD ($) $ in Millions	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	$ 1,124	$ 866	$ 2,202	$ 1,880
Retail
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	1,005	773	1,924	1,682
Retail \| Residential
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	479	365	967	822
Retail \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	513	396	932	836
Retail \| Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	13	12	25	24
Wholesale Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	48	42	135	89
Transmission Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	19	14	37	27
Other
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	52	37	106	82
Alternative and Other [Member]
Disaggregation of Revenue [Line Items]
Alternative revenue and other	50	45	133	88
Regulated Electric \| Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	792	677	1,490	1,354
Regulated Electric \| Retail
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	711	607	1,295	1,209
Regulated Electric \| Retail \| Residential
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	272	244	518	481
Regulated Electric \| Retail \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	426	351	752	704
Regulated Electric \| Retail \| Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	13	12	25	24
Regulated Electric \| Wholesale Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	48	42	135	89
Regulated Electric \| Transmission Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	19	14	37	27
Regulated Electric \| Other
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	14	14	23	29
Regulated Electric \| Alternative and Other [Member]
Disaggregation of Revenue [Line Items]
Alternative revenue and other	35	38	70	73
Regulated Natural Gas \| Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	323	180	691	505
Regulated Natural Gas \| Retail
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	285	157	608	452
Regulated Natural Gas \| Retail \| Residential
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	204	118	443	335
Regulated Natural Gas \| Retail \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	81	39	165	117
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	23	83	53
Regulated Natural Gas \| Alternative and Other [Member]
Disaggregation of Revenue [Line Items]
Alternative revenue and other	15	6	62	13
All Other \| Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	9	9	21	21
All Other \| Retail
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	9	9	21	21
All Other \| Retail \| Residential
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	3	3	6	6
All Other \| Retail \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contracts with Customers	6	6	15	15
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 \| Alternative and Other [Member]
Disaggregation of Revenue [Line Items]
Alternative revenue and other	0	1	1	2
Total revenues
Disaggregation of Revenue [Line Items]
Total revenues	1,174	911	2,335	1,968
Total revenues \| Regulated Electric
Disaggregation of Revenue [Line Items]
Total revenues	827	715	1,560	1,427
Total revenues \| Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Total revenues	338	186	753	518
Total revenues \| All Other
Disaggregation of Revenue [Line Items]
Total revenues	$ 9	$ 10	$ 22	$ 23