Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 8,489	$ 7,380
Mark-to-market for economic hedging activities	331	472
Contract amortization	(108)	(65)
Revenue	8,585	7,429
Less: Revenues accounted for under topics other than ASC 606 and ASC 815	65	16
Derivative revenue	327	468
Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	(21)	(3)
Revenue	(20)	(6)
Less: Revenues accounted for under topics other than ASC 606 and ASC 815	0	0
Retail revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	8,216	7,229
Derivative revenue	11	10
Retail revenue \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	(16)	0
Derivative revenue	0	0
Energy revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	245	152
Derivative revenue	18	62
Energy revenue \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	(1)	(3)
Derivative revenue	0	(3)
Capacity revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	47	42
Derivative revenue	16	22
Capacity revenue \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	(1)	(1)
Derivative revenue	0	0
Derivative revenue
Disaggregation of Revenue [Line Items]
Mark-to-market for economic hedging activities	(15)	(60)
Less: Realized and unrealized ASC 815 revenue	31	33
Derivative revenue \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Mark-to-market for economic hedging activities	2	0
Less: Realized and unrealized ASC 815 revenue	1	(3)
Other revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	97	76
Contract amortization	(5)	(10)
Other revenue \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	(4)	(2)
Contract amortization	0	0
Total operating revenue
Disaggregation of Revenue [Line Items]
Revenue	8,585	7,429
Total operating revenue \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Revenue	(20)	(6)
Other revenue, derivative
Disaggregation of Revenue [Line Items]
Derivative revenue	1	(1)
Other revenue, derivative \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Derivative revenue	(1)	0
Home \| Retail revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,260	3,129
Home \| Retail revenue \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	(16)	0
Business \| Retail revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,956	4,100
Business \| Retail revenue \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Texas \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,437	2,231
Revenue	2,435	2,233
Less: Revenues accounted for under topics other than ASC 606 and ASC 815	0	0
Texas \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Revenue	(7)	(1)
Texas \| Retail revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,387	2,178
Derivative revenue	0	0
Texas \| Energy revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7	7
Derivative revenue	0	0
Texas \| Capacity revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Derivative revenue	0	0
Texas \| Derivative revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Mark-to-market for economic hedging activities	0	0
Less: Realized and unrealized ASC 815 revenue	(2)	2
Texas \| Other revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	41	48
Contract amortization	0	0
Texas \| Total operating revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue	2,435	2,233
Texas \| Other revenue, derivative \| Operating Segments
Disaggregation of Revenue [Line Items]
Derivative revenue	(2)	2
Texas \| Home \| Retail revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,555	1,360
Texas \| Business \| Retail revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	832	818
East \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,514	3,481
Revenue	4,577	3,515
Less: Revenues accounted for under topics other than ASC 606 and ASC 815	37	10
East \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Revenue	1	0
East \| Retail revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,350	3,428
Derivative revenue	11	10
East \| Energy revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	158	81
Derivative revenue	14	43
East \| Capacity revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	40	41
Derivative revenue	16	22
East \| Derivative revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Mark-to-market for economic hedging activities	(19)	(51)
Less: Realized and unrealized ASC 815 revenue	26	24
East \| Other revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	53	26
Contract amortization	(5)	(10)
East \| Total operating revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue	4,577	3,515
East \| Other revenue, derivative \| Operating Segments
Disaggregation of Revenue [Line Items]
Derivative revenue	4	0
East \| Home \| Retail revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	738	702
East \| Business \| Retail revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,612	2,726
West/Services/Other \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,065	1,203
Revenue	1,099	1,219
Less: Revenues accounted for under topics other than ASC 606 and ASC 815	28	6
West/Services/Other \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Revenue	(2)	(5)
West/Services/Other \| Retail revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,001	1,155
Derivative revenue	0	0
West/Services/Other \| Energy revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	81	67
Derivative revenue	4	22
West/Services/Other \| Capacity revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	8	2
Derivative revenue	0	0
West/Services/Other \| Derivative revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Mark-to-market for economic hedging activities	2	(9)
Less: Realized and unrealized ASC 815 revenue	6	10
West/Services/Other \| Other revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7	4
Contract amortization	0	0
West/Services/Other \| Total operating revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue	1,099	1,219
West/Services/Other \| Other revenue, derivative \| Operating Segments
Disaggregation of Revenue [Line Items]
Derivative revenue	0	(3)
West/Services/Other \| Home \| Retail revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	489	599
West/Services/Other \| Business \| Retail revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	512	556
Vivint Smart Home \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	494	468
Revenue	494	468
Less: Revenues accounted for under topics other than ASC 606 and ASC 815	0	0
Vivint Smart Home \| Corporate/Eliminations
Disaggregation of Revenue [Line Items]
Revenue	(12)	0
Vivint Smart Home \| Retail revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	494	468
Derivative revenue	0	0
Vivint Smart Home \| Energy revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Derivative revenue	0	0
Vivint Smart Home \| Capacity revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Derivative revenue	0	0
Vivint Smart Home \| Derivative revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Mark-to-market for economic hedging activities	0	0
Less: Realized and unrealized ASC 815 revenue	0	0
Vivint Smart Home \| Other revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0
Contract amortization	0	0
Vivint Smart Home \| Total operating revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue	494	468
Vivint Smart Home \| Other revenue, derivative \| Operating Segments
Disaggregation of Revenue [Line Items]
Derivative revenue	0	0
Vivint Smart Home \| Home \| Retail revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	494	468
Vivint Smart Home \| Business \| Retail revenue \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 0	$ 0

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- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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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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