v3.25.2
Significant Accounting Policies - (Schedule of Revision of Previously Issued Consolidated Statements of Income and Statements of Comprehensive Income) (Parenthetical) (Details) - 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]        
Changes in unrealized net gains (losses) on investment securities, tax $ (1) $ (4) $ (8) $ 10
Virginia Electric and Power Company        
Error Corrections and Prior Period Adjustments Restatement [Line Items]        
Changes in unrealized net gains (losses) on investment securities, tax $ 0 (1) $ 0 1
As Previously Reported        
Error Corrections and Prior Period Adjustments Restatement [Line Items]        
Changes in unrealized net gains (losses) on investment securities, tax   (2)   8
As Previously Reported | Virginia Electric and Power Company        
Error Corrections and Prior Period Adjustments Restatement [Line Items]        
Changes in unrealized net gains (losses) on investment securities, tax   0   1
Adjustments        
Error Corrections and Prior Period Adjustments Restatement [Line Items]        
Changes in unrealized net gains (losses) on investment securities, tax   (2)   2
Adjustments | Virginia Electric and Power Company        
Error Corrections and Prior Period Adjustments Restatement [Line Items]        
Changes in unrealized net gains (losses) on investment securities, tax   $ (1)   $ 0