v3.25.2
Fair Value Measurements (Assets and Liabilities that are Measured at Fair Value on a Recurring Basis) (Detail) - USD ($)
$ in Millions
Jun. 30, 2025
Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets $ 746 $ 1,399
Total derivative liabilities 204 512
Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 321 375
Total derivative liabilities 63 225
Fair Value, Measurements, Recurring    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets 8,998 9,259
Total liabilities 204 512
Fair Value, Measurements, Recurring | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets 4,714 4,563
Total liabilities 63 225
Fair Value, Measurements, Recurring | Equity securities: | U.S.    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 5,732 5,405
Fair Value, Measurements, Recurring | Equity securities: | U.S. | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 2,947 2,771
Fair Value, Measurements, Recurring | Equity securities: | International    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 173 165
Fair Value, Measurements, Recurring | Equity securities: | International | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 101 99
Fair Value, Measurements, Recurring | Fixed Income | Corporate debt instruments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 550 518
Fair Value, Measurements, Recurring | Fixed Income | Corporate debt instruments | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 309 294
Fair Value, Measurements, Recurring | Fixed Income | Government Securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 1,764 1,743
Fair Value, Measurements, Recurring | Fixed Income | Government Securities | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 1,036 1,024
Fair Value, Measurements, Recurring | Cash Equivalents and Other    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 33 29
Fair Value, Measurements, Recurring | Cash Equivalents and Other | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Foreign Currency Exchange Rate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 44 30
Total derivative liabilities 9 192
Fair Value, Measurements, Recurring | Foreign Currency Exchange Rate | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 44 30
Total derivative liabilities 9 192
Fair Value, Measurements, Recurring | Commodity    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 519 494
Total derivative liabilities 129 123
Fair Value, Measurements, Recurring | Commodity | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 206 115
Total derivative liabilities 38 33
Fair Value, Measurements, Recurring | Interest Rate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 183 875
Total derivative liabilities 66 197
Fair Value, Measurements, Recurring | Interest Rate | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 71 230
Total derivative liabilities 16 0
Fair Value, Measurements, Recurring | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets 6,071 5,735
Total liabilities 0 0
Fair Value, Measurements, Recurring | Level 1 | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets 3,132 2,953
Total liabilities 0 0
Fair Value, Measurements, Recurring | Level 1 | Equity securities: | U.S.    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 5,730 5,403
Fair Value, Measurements, Recurring | Level 1 | Equity securities: | U.S. | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 2,945 2,769
Fair Value, Measurements, Recurring | Level 1 | Equity securities: | International    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 173 165
Fair Value, Measurements, Recurring | Level 1 | Equity securities: | International | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 101 99
Fair Value, Measurements, Recurring | Level 1 | Fixed Income | Corporate debt instruments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 1 | Fixed Income | Corporate debt instruments | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 1 | Fixed Income | Government Securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 135 138
Fair Value, Measurements, Recurring | Level 1 | Fixed Income | Government Securities | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 86 85
Fair Value, Measurements, Recurring | Level 1 | Cash Equivalents and Other    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 33 29
Fair Value, Measurements, Recurring | Level 1 | Cash Equivalents and Other | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 1 | Foreign Currency Exchange Rate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 0 0
Total derivative liabilities 0 0
Fair Value, Measurements, Recurring | Level 1 | Foreign Currency Exchange Rate | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 0 0
Total derivative liabilities 0 0
Fair Value, Measurements, Recurring | Level 1 | Commodity    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 0 0
Total derivative liabilities 0 0
Fair Value, Measurements, Recurring | Level 1 | Commodity | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 0 0
Total derivative liabilities 0 0
Fair Value, Measurements, Recurring | Level 1 | Interest Rate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 0 0
Total derivative liabilities 0 0
Fair Value, Measurements, Recurring | Level 1 | Interest Rate | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 0 0
Total derivative liabilities 0 0
Fair Value, Measurements, Recurring | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets 2,491 3,125
Total liabilities 182 497
Fair Value, Measurements, Recurring | Level 2 | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets 1,399 1,540
Total liabilities 59 223
Fair Value, Measurements, Recurring | Level 2 | Equity securities: | U.S.    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 2 2
Fair Value, Measurements, Recurring | Level 2 | Equity securities: | U.S. | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 2 2
Fair Value, Measurements, Recurring | Level 2 | Equity securities: | International    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 2 | Equity securities: | International | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 2 | Fixed Income | Corporate debt instruments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 550 518
Fair Value, Measurements, Recurring | Level 2 | Fixed Income | Corporate debt instruments | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 309 294
Fair Value, Measurements, Recurring | Level 2 | Fixed Income | Government Securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 1,629 1,605
Fair Value, Measurements, Recurring | Level 2 | Fixed Income | Government Securities | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 950 939
Fair Value, Measurements, Recurring | Level 2 | Cash Equivalents and Other    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 2 | Cash Equivalents and Other | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 2 | Foreign Currency Exchange Rate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 44 30
Total derivative liabilities 9 192
Fair Value, Measurements, Recurring | Level 2 | Foreign Currency Exchange Rate | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 44 30
Total derivative liabilities 9 192
Fair Value, Measurements, Recurring | Level 2 | Commodity    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 83 95
Total derivative liabilities 107 108
Fair Value, Measurements, Recurring | Level 2 | Commodity | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 23 45
Total derivative liabilities 34 31
Fair Value, Measurements, Recurring | Level 2 | Interest Rate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 183 875
Total derivative liabilities 66 197
Fair Value, Measurements, Recurring | Level 2 | Interest Rate | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 71 230
Total derivative liabilities 16 0
Fair Value, Measurements, Recurring | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets 436 399
Total liabilities 22 15
Fair Value, Measurements, Recurring | Level 3 | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total assets 183 70
Total liabilities 4 2
Fair Value, Measurements, Recurring | Level 3 | Equity securities: | U.S.    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 3 | Equity securities: | U.S. | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 3 | Equity securities: | International    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 3 | Equity securities: | International | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 3 | Fixed Income | Corporate debt instruments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 3 | Fixed Income | Corporate debt instruments | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 3 | Fixed Income | Government Securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 3 | Fixed Income | Government Securities | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 3 | Cash Equivalents and Other    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 3 | Cash Equivalents and Other | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments [1] 0 0
Fair Value, Measurements, Recurring | Level 3 | Foreign Currency Exchange Rate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 0 0
Total derivative liabilities 0 0
Fair Value, Measurements, Recurring | Level 3 | Foreign Currency Exchange Rate | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 0 0
Total derivative liabilities 0 0
Fair Value, Measurements, Recurring | Level 3 | Commodity    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 436 399
Total derivative liabilities 22 15
Fair Value, Measurements, Recurring | Level 3 | Commodity | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 183 70
Total derivative liabilities 4 2
Fair Value, Measurements, Recurring | Level 3 | Interest Rate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 0 0
Total derivative liabilities 0 0
Fair Value, Measurements, Recurring | Level 3 | Interest Rate | Virginia Electric and Power Company    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total derivative assets 0 0
Total derivative liabilities $ 0 $ 0
[1] Includes investments held in the nuclear decommissioning trusts and rabbi trusts. Excludes $208 million and $212 million of assets at Dominion Energy, inclusive of $74 million and $76 million at Virginia Power, at June 30, 2025 and December 31, 2024, respectively, measured at fair value using NAV (or its equivalent) as a practical expedient which are not required to be categorized in the fair value hierarchy.