v3.25.2
Income Taxes (Reconciliation of Income Taxes at the U.S. Statutory Federal Income Tax Rate) (Detail)
6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Effective Income Tax Computation [Line Items]    
U.S. statutory rate 21.00% 21.00%
Increases (reductions) resulting from:    
State taxes, net of federal benefit 4.70% 2.80%
Investment tax credits (2.50%) (1.80%)
Production tax credits (4.90%) (3.00%)
Reversal of excess deferred income taxes (1.70%) (3.20%)
Qualified nuclear decommissioning trust net gains (losses) 2.00% 6.00%
Remeasurements and settlements of uncertain tax positions (1.60%)  
AFUDC - equity (0.80%) (0.90%)
Absence of tax on noncontrolling interest (1.60%)  
Other, net (0.10%) 0.80%
Effective tax rate 14.50% 21.70%
Virginia Electric and Power Company    
Effective Income Tax Computation [Line Items]    
U.S. statutory rate 21.00% 21.00%
Increases (reductions) resulting from:    
State taxes, net of federal benefit 4.40% 4.40%
Investment tax credits (0.80%) (0.80%)
Production tax credits (4.10%) (2.00%)
Reversal of excess deferred income taxes (1.70%) (1.70%)
AFUDC - equity (1.00%) (0.60%)
Absence of tax on noncontrolling interest (2.30%)  
Other, net (0.10%) 1.00%
Effective tax rate 15.40% 21.30%