v3.25.2
Operating Segments - Dominion Energy (Narrative) (Detail) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Mar. 31, 2024
Jun. 30, 2025
Jun. 30, 2024
Segment Reporting Information [Line Items]      
Gain (loss) on investments   $ 173 $ 395
Charge in connection with settlement of an agreement $ 47    
Charge in connection with settlement of an agreement, after tax $ 35    
Operating Segments      
Segment Reporting Information [Line Items]      
After- tax net benefits (expenses)   (7) 19
Gain (loss) on investments   156 348
Gain (loss) on investments, after tax   $ 87 $ 216
Investment, Type [Extensible Enumeration]   Nuclear Decommissioning Trust Fund [Member] Nuclear Decommissioning Trust Fund [Member]
Corporate and Other | Operating Segments      
Segment Reporting Information [Line Items]      
After- tax net benefits (expenses)   $ (102) $ (314)
After- tax net benefits (expenses) for specific items   (27) (86)
Contracted Energy | Operating Segments      
Segment Reporting Information [Line Items]      
Gain (loss) on investments, after tax   74 187
Gain (loss) related to economic hedging activities   26 (167)
Gain (loss) related to economic hedging activities after tax   19 (127)
Charge in connection with settlement of an agreement     47
Charge in connection with settlement of an agreement, after tax     35
Charge for impairment of nonregulated renewable natural gas facilities     33
Charge for impairment of nonregulated renewable natural gas facilities after tax     25
Dominion Energy Virginia | Operating Segments      
Segment Reporting Information [Line Items]      
Gain (loss) on investments, after tax   $ 13 $ 29
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   $ 48  
Share of costs not expected to be recovered from customers on the CVOW commercial project, after tax   36  
Loss associated with severe weather events   106  
Loss associated with severe weather events, after-tax   $ 79