v3.25.2
Significant Accounting Policies (Schedule of Revision of Previously Issued Consolidated Statements of Cash Flows) (Detail) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Error Corrections and Prior Period Adjustments Restatement [Line Items]        
Net income including noncontrolling interests $ 814 $ 563 $ 1,525 $ 966
Operating Activities        
Deferred income taxes     192 (74)
Other operating assets and liabilities     (46) (292)
Net cash provided by operating activities     2,429 2,838
As Previously Reported        
Error Corrections and Prior Period Adjustments Restatement [Line Items]        
Net income including noncontrolling interests   580   1,021
Operating Activities        
Deferred income taxes       (128)
Other operating assets and liabilities       (293)
Net cash provided by operating activities       2,838
Adjustments        
Error Corrections and Prior Period Adjustments Restatement [Line Items]        
Net income including noncontrolling interests   (17)   (55)
Operating Activities        
Deferred income taxes       54
Other operating assets and liabilities       (1)
Net cash provided by operating activities       0
Virginia Electric And Power Company [Member]        
Error Corrections and Prior Period Adjustments Restatement [Line Items]        
Net income including noncontrolling interests $ 589 477 1,120 938
Operating Activities        
Deferred income taxes     176 302
Other operating assets and liabilities     143 (133)
Net cash provided by operating activities     $ 1,834 2,434
Virginia Electric And Power Company [Member] | As Previously Reported        
Error Corrections and Prior Period Adjustments Restatement [Line Items]        
Net income including noncontrolling interests   479   944
Operating Activities        
Deferred income taxes       296
Other operating assets and liabilities       (133)
Net cash provided by operating activities       2,434
Virginia Electric And Power Company [Member] | Adjustments        
Error Corrections and Prior Period Adjustments Restatement [Line Items]        
Net income including noncontrolling interests   $ (2)   (6)
Operating Activities        
Deferred income taxes       6
Other operating assets and liabilities       0
Net cash provided by operating activities       $ 0