v3.25.2
Related-Party Transactions (Parenthetical) (Detail) - Virginia Electric and Power Company - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Related Party Transaction [Line Items]        
Capital expenditures     $ 5,103 $ 4,489
Services provided by affiliates | Affiliated Entity        
Related Party Transaction [Line Items]        
Capital expenditures $ 71 $ 58 $ 146 $ 111