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No definition available.

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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, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Operating Segments
Disaggregation of Revenue [Line Items]
Total revenues	$ 3,182	$ 3,013	$ 8,579	$ 8,731
Regulated Electric \| Operating Segments
Disaggregation of Revenue [Line Items]
Total revenues	2,941	2,771	7,430	7,345
Regulated Natural Gas \| Operating Segments
Disaggregation of Revenue [Line Items]
Total revenues	219	222	1,082	1,324
All Other \| Operating Segments
Disaggregation of Revenue [Line Items]
Total revenues	22	20	67	62
Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,963	2,875	8,078	8,378
Total revenue from contracts with customers \| Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,737	2,652	6,981	7,037
Total revenue from contracts with customers \| Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	208	206	1,041	1,288
Total revenue from contracts with customers \| All Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	18	17	56	53
Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,534	2,482	6,942	7,295
Retail \| Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,097	999	3,035	3,046
Retail \| C&I
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,401	1,447	3,809	4,148
Retail \| Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	36	36	98	101
Retail \| Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,336	2,283	5,931	6,038
Retail \| Regulated Electric \| Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	962	865	2,356	2,216
Retail \| Regulated Electric \| C&I
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,340	1,383	3,481	3,724
Retail \| Regulated Electric \| Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	34	35	94	98
Retail \| Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	180	182	955	1,204
Retail \| Regulated Natural Gas \| Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	124	124	647	801
Retail \| Regulated Natural Gas \| C&I
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	56	58	308	403
Retail \| Regulated Natural Gas \| Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Retail \| All Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	18	17	56	53
Retail \| All Other \| Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	11	10	32	29
Retail \| All Other \| C&I
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5	6	20	21
Retail \| All Other \| Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2	1	4	3
Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	227	205	553	548
Wholesale \| Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	227	205	553	548
Wholesale \| Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Wholesale \| All Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Transmission
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	157	151	442	409
Transmission \| Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	157	151	442	409
Transmission \| Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Transmission \| All Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	45	37	141	126
Other \| Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	17	13	55	42
Other \| Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	28	24	86	84
Other \| All Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Alternative revenue and other
Disaggregation of Revenue [Line Items]
Alternative revenue and other	219	138	501	353
Alternative revenue and other \| Regulated Electric
Disaggregation of Revenue [Line Items]
Alternative revenue and other	204	119	449	308
Alternative revenue and other \| Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Alternative revenue and other	11	16	41	36
Alternative revenue and other \| All Other
Disaggregation of Revenue [Line Items]
Alternative revenue and other	$ 4	$ 3	$ 11	$ 9