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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		6 Months Ended
Revenues (Details) - USD ($) $ in Millions	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Operating Segments
Disaggregation of Revenue [Line Items]
Total revenues	$ 2,586	$ 2,577	$ 5,397	$ 5,718
Regulated Electric \| Operating Segments
Disaggregation of Revenue [Line Items]
Total revenues	2,286	2,249	4,489	4,574
Regulated Natural Gas \| Operating Segments
Disaggregation of Revenue [Line Items]
Total revenues	280	308	863	1,102
All Other \| Operating Segments
Disaggregation of Revenue [Line Items]
Total revenues	20	20	45	42
Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,441	2,463	5,115	5,503
Total revenue from contracts with customers \| Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,158	2,148	4,244	4,385
Total revenue from contracts with customers \| Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	266	298	833	1,082
Total revenue from contracts with customers \| All Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	17	17	38	36
Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,081	2,145	4,408	4,813
Retail \| Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	895	816	1,937	2,047
Retail \| C&I
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,154	1,297	2,409	2,701
Retail \| Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	32	32	62	65
Retail \| Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,824	1,856	3,595	3,755
Retail \| Regulated Electric \| Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	718	624	1,394	1,351
Retail \| Regulated Electric \| C&I
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,075	1,201	2,141	2,341
Retail \| Regulated Electric \| Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	31	31	60	63
Retail \| Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	240	272	775	1,022
Retail \| Regulated Natural Gas \| Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	167	182	522	677
Retail \| Regulated Natural Gas \| C&I
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	73	90	253	345
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	17	17	38	36
Retail \| All Other \| Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	10	10	21	19
Retail \| All Other \| C&I
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	6	6	15	15
Retail \| All Other \| Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1	1	2	2
Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	160	154	326	343
Wholesale \| Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	160	154	326	343
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	153	127	285	258
Transmission \| Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	153	127	285	258
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	47	37	96	89
Other \| Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	21	11	38	29
Other \| Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	26	26	58	60
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	145	114	282	215
Alternative revenue and other \| Regulated Electric
Disaggregation of Revenue [Line Items]
Alternative revenue and other	128	101	245	189
Alternative revenue and other \| Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Alternative revenue and other	14	10	30	20
Alternative revenue and other \| All Other
Disaggregation of Revenue [Line Items]
Alternative revenue and other	$ 3	$ 3	$ 7	$ 6