v3.26.1
Operating Segments - Dominion Energy (Narrative) (Detail)
$ in Millions
 6 Months Ended
Jun. 30, 2026
USD ($)
Segment
Jun. 30, 2025
USD ($)
Segment Reporting Information [Line Items]    
Number of operating segment | Segment 3  
Number of reportable segment | Segment 3  
Gains (loss) on investments $ 350 $ 173
Virginia Electric and Power Company    
Segment Reporting Information [Line Items]    
Number of operating segment | Segment 1  
Number of reportable segment | Segment 1  
Gains (loss) on investments $ 48 24
Operating Segments    
Segment Reporting Information [Line Items]    
After- tax net benefits (expenses) (607) (7)
Gains (loss) on investments 341 156
Gains (loss) on investments, after tax $ 221 $ 87
Investment, Type [Extensible Enumeration] Nuclear Decommissioning Trust Fund [Member] Nuclear Decommissioning Trust Fund [Member]
Operating Segments | Virginia Electric and Power Company    
Segment Reporting Information [Line Items]    
Gains (loss) on investments $ 53 $ 23
Gains (loss) on investments, after tax $ 31 $ 13
Investment, Type [Extensible Enumeration] Nuclear Decommissioning Trust Fund [Member] Nuclear Decommissioning Trust Fund [Member]
Share of costs not expected to be recovered from customers on the CVOW commercial project $ 65 $ 48
Share of costs not expected to be recovered from customers on the CVOW commercial project, after tax 48 36
Loss associated with severe weather events 116 106
Loss associated with severe weather events, after-tax 86 79
Charge for the disallowance of certain strategic undergrounding costs 24  
Charge for the disallowance of certain strategic undergrounding costs, net of tax 18  
Corporate and Other | Operating Segments    
Segment Reporting Information [Line Items]    
After- tax net benefits (expenses) (760) (102)
After- tax net benefits (expenses) for specific items (598) (27)
Corporate and Other | Operating Segments | Virginia Electric and Power Company    
Segment Reporting Information [Line Items]    
After- tax net benefits (expenses) (120) (90)
After- tax net benefits (expenses) for specific items (129) (100)
Contracted Energy | Operating Segments    
Segment Reporting Information [Line Items]    
Gains (loss) on investments, after tax 190 74
Gain (losses) related to economic hedging activities (141) 26
Gain (losses) related to economic hedging activities after tax (106) 19
Charge associated with certain nonregulated solar generation facilities 78  
Charge associated with certain nonregulated solar generation facilities, net of tax 60  
Charge for the impairment of nonregulated renewable natural gas facilities 820  
Charge for the impairment of nonregulated renewable natural gas facilities, net of tax 640  
Benefit related to the revision of aros for millstone unit 1 195  
Benefit related to the revision of aros for millstone unit 1, net of tax 142  
Dominion Energy Virginia | Operating Segments    
Segment Reporting Information [Line Items]    
Gains (loss) on investments, after tax $ 31 $ 13
Investment, Type [Extensible Enumeration] Nuclear Decommissioning Trust Fund [Member] Nuclear Decommissioning Trust Fund [Member]
Share of costs not expected to be recovered from customers on the CVOW commercial project $ 65 $ 48
Share of costs not expected to be recovered from customers on the CVOW commercial project, after tax 48 36
Loss associated with severe weather events 116 106
Loss associated with severe weather events, after-tax 86 $ 79
Charge for the disallowance of certain strategic undergrounding costs 24  
Charge for the disallowance of certain strategic undergrounding costs, net of tax $ 18