v3.26.1
Investments (Summary of Nuclear Decommissioning Trust Funds to Fund Future Decommissioning Costs and Nuclear Plants) (Detail) - USD ($)
$ in Millions
 6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Debt Securities, Available-for-Sale [Line Items]    
Fixed income securities Fair Value $ 864  
Cash equivalents and other, Amortized Cost [1] 55 $ 7
Cash equivalents and other, Total Unrealized Gains [1] 0 0
Cash equivalents and other, Total Unrealized Losses [1] 0 0
Cash equivalents and other, Allowance for Credit Losses [1] 0 0
Cash equivalents and other, Fair Value [1] 55 7
Amortized Cost, Total 4,075 3,994
Total Unrealized Gains 5,836 5,174
Total Unrealized Losses [2] (4) (2)
Allowance for Credit Losses, Total 0 0
Fair Value, Total 9,907 9,166 [3]
Net assets related to pending purchases of securities   40
Net assets related to pending sale of securities 7  
Fair value of securities in an unrealized loss position 192 48
Virginia Electric and Power Company    
Debt Securities, Available-for-Sale [Line Items]    
Fixed income securities Fair Value 590  
Cash equivalents and other, Amortized Cost [1] 4 3
Cash equivalents and other, Total Unrealized Gains [1] 0 0
Cash equivalents and other, Total Unrealized Losses [1] 0 0
Cash equivalents and other, Allowance for Credit Losses [1] 0 0
Cash equivalents and other, Fair Value [1] 4 3
Amortized Cost, Total 2,222 2,177
Total Unrealized Gains 3,054 2,689
Total Unrealized Losses [2] (3) (2)
Allowance for Credit Losses, Total 0 0
Fair Value, Total 5,273 4,864 [4]
Net assets related to pending sale of securities 4 3
Fair value of securities in an unrealized loss position 120 3
Government Debt Fixed Income Securities    
Debt Securities, Available-for-Sale [Line Items]    
Fixed income securities Amortized Cost, Total [5] 318 448
Fixed income securities Total Unrealized Gains [5] 1 0
Fixed income securities Total Unrealized Losses [5] (1) 0
Fixed income securities Allowance for Credit Losses [5] 0 0
Fixed income securities Fair Value [5] 318 448
Government Debt Fixed Income Securities | Virginia Electric and Power Company    
Debt Securities, Available-for-Sale [Line Items]    
Fixed income securities Amortized Cost, Total [5] 226 332
Fixed income securities Total Unrealized Gains [5] 1 0
Fixed income securities Total Unrealized Losses [5] 0 0
Fixed income securities Allowance for Credit Losses [5] 0 0
Fixed income securities Fair Value [5] 227 332
Corporate Debt Fixed Income Securities    
Debt Securities, Available-for-Sale [Line Items]    
Fixed income securities Amortized Cost, Total [5] 126  
Fixed income securities Total Unrealized Gains [5] 1  
Fixed income securities Total Unrealized Losses [5] 0  
Fixed income securities Allowance for Credit Losses [5] 0  
Fixed income securities Fair Value [5] 127  
Corporate Debt Fixed Income Securities | Virginia Electric and Power Company    
Debt Securities, Available-for-Sale [Line Items]    
Fixed income securities Amortized Cost, Total [5] 126  
Fixed income securities Total Unrealized Gains [5] 1  
Fixed income securities Total Unrealized Losses [5] 0  
Fixed income securities Allowance for Credit Losses [5] 0  
Fixed income securities Fair Value [5] 127  
Private Debt Funds    
Debt Securities, Available-for-Sale [Line Items]    
Fixed income securities Amortized Cost, Total [6] 2,199 [5] 2,143
Fixed income securities Total Unrealized Gains [6] 28 [5] 0
Fixed income securities Total Unrealized Losses [6] 0 [5] 0
Fixed income securities Allowance for Credit Losses [6] 0 [5] 0
Fixed income securities Fair Value [6] 2,227 [5] 2,143
Private Debt Funds | Virginia Electric and Power Company    
Debt Securities, Available-for-Sale [Line Items]    
Fixed income securities Amortized Cost, Total [6] 1,244 [5] 1,213
Fixed income securities Total Unrealized Gains [6] 16 [5] 0
Fixed income securities Total Unrealized Losses [6] 0 [5] 0
Fixed income securities Allowance for Credit Losses [6] 0 [5] 0
Fixed income securities Fair Value [6] 1,260 [5] 1,213
Insurance Contracts    
Debt Securities, Available-for-Sale [Line Items]    
Fixed income securities Amortized Cost, Total [7] 253 245
Fixed income securities Total Unrealized Gains [7] 0 0
Fixed income securities Total Unrealized Losses [7] 0 0
Fixed income securities Allowance for Credit Losses [7] 0 0
Fixed income securities Fair Value [7] 253 245
Insurance Contracts | Virginia Electric and Power Company    
Debt Securities, Available-for-Sale [Line Items]    
Fixed income securities Amortized Cost, Total [7]   0
Fixed income securities Total Unrealized Gains [7]   0
Fixed income securities Total Unrealized Losses [7]   0
Fixed income securities Allowance for Credit Losses [7]   0
Fixed income securities Fair Value [7]   0
U.S.    
Debt Securities, Available-for-Sale [Line Items]    
Equity securities Amortized Cost [8] 1,081 1,107
Equity securities Total Unrealized Gains [8] 5,658 5,052
Equity securities Total Unrealized Losses [8] (3) (2)
Equity securities Fair Value [8] 6,736 6,157
U.S. | Virginia Electric and Power Company    
Debt Securities, Available-for-Sale [Line Items]    
Equity securities Amortized Cost [8] 596 602
Equity securities Total Unrealized Gains [8] 2,961 2,620
Equity securities Total Unrealized Losses [8] (3) (2)
Equity securities Fair Value [8] 3,554 3,220
International    
Debt Securities, Available-for-Sale [Line Items]    
Equity securities Amortized Cost [8] 43 44
Equity securities Total Unrealized Gains [8] 148 122
Equity securities Total Unrealized Losses [8] 0 0
Equity securities Fair Value [8] 191 166
International | Virginia Electric and Power Company    
Debt Securities, Available-for-Sale [Line Items]    
Equity securities Amortized Cost [8] 26 27
Equity securities Total Unrealized Gains [8] 75 69
Equity securities Total Unrealized Losses [8] 0 0
Equity securities Fair Value [8] $ 101 $ 96
[1] Dominion Energy includes pending sales of securities of $7 million and pending purchases of securities of $40 million at June 30, 2026 and December 31, 2025, respectively. Virginia Power includes pending sales of securities of $4 million and $3 million at June 30, 2026, and December 31, 2025, respectively.
[2] Dominion Energy’s fair value of securities in an unrealized loss position was $192 million and $48 million at June 30, 2026 and December 31, 2025, respectively. Virginia Power’s fair value of securities in an unrealized loss position was $120 million and $3 million at June 30, 2026 and December 31, 2025, respectively.
[3] Dominion Energy’s Consolidated Balance Sheet at December 31, 2025 has been derived from the audited Consolidated Balance Sheet at that date.
[4] Virginia Power’s Consolidated Balance Sheet at December 31, 2025 has been derived from the audited Consolidated Balance Sheet at that date.
[5] Unrealized gains and losses on fixed income securities are included in AOCI and the nuclear decommissioning trust regulatory liability. Changes in allowance for credit losses are included in other income (expense).
[6] These private debt funds are generally structured without an explicit termination date. The Companies’ withdrawal and redemption rights begin after an initial multiyear lock-up period. Unless otherwise elected, distributions of income, profits and capital are generally reinvested in the underlying funds. The Companies may elect to receive a portion of future income as cash distributions, subject to fund liquidity restrictions. Generally, the Companies’ interests can be sold in the secondary markets subject to the approval of the general partner. Secondary markets tend to be less liquid especially during periods of market stress.
[7] Includes company owned life insurance contracts measured at cash surrender value.
[8] Unrealized gains and losses on equity securities are included in other income (expense) and the nuclear decommissioning trust regulatory liability.