v3.26.3
Significant Financing Transactions (Narrative) (Detail) - USD ($)
 1 Months Ended 3 Months Ended 9 Months Ended 12 Months Ended
Jul. 31, 2026
Jun. 30, 2026
Apr. 30, 2026
Aug. 31, 2025
Jun. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Dec. 31, 2025
Oct. 31, 2026
Oct. 30, 2026
Aug. 31, 2026
May 31, 2026
Mar. 31, 2026
Feb. 28, 2026
Jan. 31, 2026
Oct. 31, 2025
Mar. 31, 2023
Nov. 30, 2020
Nov. 30, 2017
Debt Instrument [Line Items]                                          
Facility Limit           $ 8,000,000,000   $ 8,000,000,000                          
Repayment of supplemental credit facility borrowings               1,250,000,000 $ 0                        
Supplemental credit facility borrowings           0   0   $ 0 [1]                      
Short-term debt           $ 3,308,000,000   3,308,000,000   2,457,000,000 [1]                      
Line of credit issued               $ 1,250,000,000 0                        
Preferred stock shares authorized           20,000,000   20,000,000                          
Dividend stock           $ 11,000,000 $ 11,000,000 $ 33,000,000 33,000,000                        
Issuance of common stock               40,000,000 105,000,000                        
Issuance of common stock           2,000,000 $ 35,000,000 $ 40,000,000 $ 105,000,000                        
Period of deferral   10 years                                      
Common Stock                                          
Debt Instrument [Line Items]                                          
Stock repurchased, shares               0                          
Issuance of stock (in shares)             1,000,000 1,000,000 2,000,000                        
Issuance of common stock           2,000,000 $ 35,000,000 $ 40,000,000 $ 105,000,000                        
Stock repurchase program, authorized amount           900,000,000   900,000,000                       $ 1,000,000,000  
Various Programs                                          
Debt Instrument [Line Items]                                          
Issuance of common stock               $ 40,000,000 105,000,000                        
Issuance of stock (in shares)               1,000,000                          
Credit Facility Maturing In April 2029                                          
Debt Instrument [Line Items]                                          
Line of credit facility, maturity month and year               2029-04                          
Floating Rate Demand Notes                                          
Debt Instrument [Line Items]                                          
Short-term debt           $ 369,000,000   $ 369,000,000   422,000,000                      
Floating Rate Demand Notes | Shelf Registration for Sale of Demand Notes                                          
Debt Instrument [Line Items]                                          
Facility Limit                                         $ 3,000,000,000
Dominion Energy South Carolina | First mortgage bonds mature in 2056                                          
Debt Instrument [Line Items]                                          
Debt instrument maturity year               2056                          
Interest Rate           6.15%   6.15%                          
Debt issued amount           $ 300,000,000   $ 300,000,000                          
Dominion Energy South Carolina | Letters of Credit Securing Industrial Revenue Bonds | Subsequent Event                                          
Debt Instrument [Line Items]                                          
Debt issued amount                       $ 68,000,000                  
Virginia Electric and Power Company                                          
Debt Instrument [Line Items]                                          
Facility Limit [2]           7,000,000,000   7,000,000,000                          
Short-term debt           $ 485,000,000   485,000,000   $ 675,000,000 [3]                      
Issuance of common stock   $ 450,000,000   $ 1,400,000,000 $ 2,100,000,000     450,000,000 3,500,000,000                        
Issuance of common stock   $ 3,600,000,000         $ 1,400,000,000 $ 450,000,000 $ 3,500,000,000                        
Virginia Electric and Power Company | Common Stock                                          
Debt Instrument [Line Items]                                          
Issuance of stock (in shares)   6,046   19,630 30,006   20,000 6,000 50,000                        
Issuance of common stock             $ 1,400,000,000 $ 450,000,000 $ 3,500,000,000                        
Virginia Electric and Power Company | Senior Notes Due in 2036                                          
Debt Instrument [Line Items]                                          
Debt instrument maturity year               2036                          
Interest Rate                         5.65%   4.95%            
Debt issued amount                         $ 1,300,000,000   $ 1,300,000,000            
Virginia Electric and Power Company | Senior Notes Due in 2056                                          
Debt Instrument [Line Items]                                          
Debt instrument maturity year               2056                          
Interest Rate                         6.30%   5.70%            
Debt issued amount                         $ 700,000,000   $ 850,000,000            
Dominion Energy | Series C Preferred Stock                                          
Debt Instrument [Line Items]                                          
Preferred stock shares outstanding           1,000,000   1,000,000   1,000,000                      
Dividend stock           $ 11,000,000 $ 11,000,000 $ 33,000,000 $ 33,000,000                        
Preferred stock dividend per share           $ 10.875 $ 10.875 $ 32.625 $ 32.625                        
Dominion Energy | Senior Notes Due in 2036                                          
Debt Instrument [Line Items]                                          
Debt instrument maturity year               2036                          
Interest Rate   5.35%                                      
Debt issued amount   $ 825,000,000                                      
Dominion Energy | Series A JSN                                          
Debt Instrument [Line Items]                                          
Debt instrument maturity year   2056                                      
Interest Rate   6.15%                                      
Interest reset period   5 years                                      
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]   us-gaap:UsTreasuryUstInterestRateMember                                      
Interest rate spread   1.869%                                      
Interest rate minimum reset   6.15%                                      
Issuance of subordinate notes   $ 1,000,000,000                                      
Dominion Energy | Series B JSN                                          
Debt Instrument [Line Items]                                          
Debt instrument maturity year   2056                                      
Interest Rate   6.25%                                      
Interest reset period   5 years                                      
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]   us-gaap:UsTreasuryUstInterestRateMember                                      
Interest rate spread   1.702%                                      
Interest rate minimum reset   6.25%                                      
Issuance of subordinate notes   $ 500,000,000                                      
Minimum | Dominion Energy                                          
Debt Instrument [Line Items]                                          
Dividends per share   $ 0.6675       $ 0.6675   $ 0.6675             $ 0.6675            
Maximum | Various Programs                                          
Debt Instrument [Line Items]                                          
Issuance of stock (in shares)                 2,000,000                        
Junior Subordinated Debt | Dominion Energy                                          
Debt Instrument [Line Items]                                          
Issuance of subordinate notes   $ 1,500,000,000                                      
May 2024 At-the-Market Program [Member] | Forward Sale Agreements                                          
Debt Instrument [Line Items]                                          
Forward sale agreements, number of shares of common stock to be settled             2,400,000   2,400,000                        
Weighted average initial forward price             $ 59.91   $ 59.91                        
February 2025 At-the-Market Program [Member] | Forward Sale Agreements                                          
Debt Instrument [Line Items]                                          
Forward sale agreements, number of shares of common stock to be settled   7,900,000     11,000,000                   3,200,000            
Weighted average initial forward price   $ 67.88     $ 55.83                   $ 62.96            
February 2025 At-the-Market Program [Member] | Forward Sale Agreement Expected to be Settled in Fourth Quarter of 2027                                          
Debt Instrument [Line Items]                                          
Forward sale agreements, number of shares of common stock to be settled             9,600,000   9,600,000                        
Weighted average initial forward price             $ 61.11   $ 61.11                        
February 2025 At-the-Market Program [Member] | Aggregate Forward Sale Agreement                                          
Debt Instrument [Line Items]                                          
Facility Limit                                   $ 1,800,000,000      
Forward sale agreements, number of shares of common stock to be settled                   5,400,000                      
February 2025 At-the-Market Program [Member] | Weighted Average | Aggregate Forward Sale Agreement                                          
Debt Instrument [Line Items]                                          
Weighted average initial forward price                   $ 60.44                      
Joint Revolving Credit Facility                                          
Debt Instrument [Line Items]                                          
Facility Limit     $ 7,000,000,000                                    
Letter of Credit                                          
Debt Instrument [Line Items]                                          
Facility Limit                                     $ 100,000,000    
Letters of credit issued and outstanding           $ 27,000,000   $ 27,000,000   $ 26,000,000                      
Letter of Credit | Credit Facility in June 2024                                          
Debt Instrument [Line Items]                                          
Facility Limit           275,000,000   275,000,000                          
Letters of credit issued and outstanding           100,000,000   100,000,000   102,000,000                      
Letter of Credit | Credit Facility In January 2026                                          
Debt Instrument [Line Items]                                          
Facility Limit $ 450,000,000                               $ 450,000,000        
Letter of Credit | Credit Facility One in September 2025                                          
Debt Instrument [Line Items]                                          
Facility Limit             $ 500,000,000   $ 500,000,000                        
Letter of Credit | Dominion Energy South Carolina | Credit Facility in June 2024                                          
Debt Instrument [Line Items]                                          
Letters of credit issued and outstanding           100,000,000   100,000,000   102,000,000                      
Letter of Credit | Dominion Energy South Carolina | Credit Facility In January 2026                                          
Debt Instrument [Line Items]                                          
Facility Limit 50,000,000                               50,000,000        
Letter of Credit | Dominion Energy South Carolina | Credit Facility One in September 2025                                          
Debt Instrument [Line Items]                                          
Facility Limit             100,000,000   100,000,000                        
Letters of credit issued and outstanding           351,000,000   351,000,000   379,000,000                      
Letter of Credit | Virginia Electric and Power Company                                          
Debt Instrument [Line Items]                                          
Facility Limit           450,000,000   450,000,000                          
Letters of credit issued and outstanding           330,000,000   330,000,000   100,000,000                      
Line of credit issued               278,000,000   281,000,000                      
Letter of Credit | Virginia Electric and Power Company | Forecast                                          
Debt Instrument [Line Items]                                          
Letters of credit issued and outstanding                     $ 317,000,000                    
Letter of Credit | Virginia Electric and Power Company | Subsequent Event                                          
Debt Instrument [Line Items]                                          
Facility Limit                       $ 500,000,000                  
Letter of Credit | Virginia Electric and Power Company | Credit Facility in June 2024                                          
Debt Instrument [Line Items]                                          
Letters of credit issued and outstanding           79,000,000   79,000,000   81,000,000                      
Letter of Credit | Virginia Electric and Power Company | Credit Facility in January 2025                                          
Debt Instrument [Line Items]                                          
Facility Limit 400,000,000                                        
Letter of Credit | Virginia Electric and Power Company | Credit Facility In January 2026                                          
Debt Instrument [Line Items]                                          
Facility Limit                                 $ 400,000,000        
Letters of credit issued and outstanding           330,000,000   330,000,000   100,000,000                      
Letter of Credit | Virginia Electric and Power Company | Credit Facility In January 2026 | Forecast                                          
Debt Instrument [Line Items]                                          
Letters of credit issued and outstanding                     317,000,000                    
Letter of Credit | Virginia Electric and Power Company | Credit Facility Two In July 2026                                          
Debt Instrument [Line Items]                                          
Facility Limit 250,000,000                                        
Letter of Credit | Virginia Electric and Power Company | Credit Facility Two In September 2026                                          
Debt Instrument [Line Items]                                          
Letters of credit issued and outstanding           0   0                          
Letter of Credit | Virginia Electric and Power Company | Credit Facility One in September 2025                                          
Debt Instrument [Line Items]                                          
Facility Limit             400,000,000   400,000,000                        
Letters of credit issued and outstanding           351,000,000   351,000,000   379,000,000                      
Letter of Credit | Virginia Electric and Power Company | Credit Facility Two in September 2025                                          
Debt Instrument [Line Items]                                          
Facility Limit           980,000,000 $ 2,000,000,000 980,000,000 $ 2,000,000,000 1,000,000,000                      
Letter of Credit | Dominion Energy                                          
Debt Instrument [Line Items]                                          
Letters of credit issued and outstanding           380,000,000   380,000,000   150,000,000                      
Letter of Credit | Dominion Energy | Forecast                                          
Debt Instrument [Line Items]                                          
Letters of credit issued and outstanding                     $ 367,000,000                    
Letter of Credit | Maximum | Virginia Electric and Power Company                                          
Debt Instrument [Line Items]                                          
Facility Limit           3,000,000,000   3,000,000,000                          
Supplemental Revolving Credit Facility                                          
Debt Instrument [Line Items]                                          
Facility Limit [4]           1,000,000,000   1,000,000,000                          
Supplemental credit facility borrowings           $ 0   $ 0   $ 0                      
Line of credit facility, maturity month and year     2028-04                                    
Sustainability Revolving Credit Facility                                          
Debt Instrument [Line Items]                                          
Facility Limit                           $ 500,000,000   $ 500,000,000          
Repayment of supplemental credit facility borrowings $ 200,000,000 $ 300,000,000                                      
Sustainability Revolving Credit Facility | Credit Facility Maturing In April 2028                                          
Debt Instrument [Line Items]                                          
Line of credit facility, maturity month and year               2028-04                          
364 Day Term Loan Facility                                          
Debt Instrument [Line Items]                                          
Facility Limit                               $ 1,300,000,000          
[1] Dominion Energy’s Consolidated Balance Sheet at December 31, 2025 has been derived from the audited Consolidated Balance Sheet at that date.
[2] The full amount of the facility is available to Virginia Power, less any amounts outstanding to co-borrowers Dominion Energy and DESC. The sub-limit for Virginia Power is set pursuant to the terms of the facility but can be changed at the option of the borrowers multiple times per year. At September 30, 2026, the sub-limit for Virginia Power was $4.0 billion. If Virginia Power has liquidity needs in excess of its current sub-limit, the sub-limit may be changed or such needs may be satisfied through short-term intercompany borrowings from Dominion Energy. This credit facility matures in April 2031 in accordance with the extension exercised by the borrowers in April 2026, with the potential to be further extended by the borrowers to April 2032, and can be used to support bank borrowings and the issuance of commercial paper, as well as to support up to $3.0 billion (or the sub-limit, whichever is less) of letters of credit, for working capital and other general corporate purposes.
[3] Virginia Power’s Consolidated Balance Sheet at December 31, 2025 has been derived from the audited Consolidated Balance Sheet at that date.
[4] This credit facility, entered into in April 2026 with certain lenders, matures in April 2028, with the potential to be extended by Dominion Energy to April 2029, contains a maximum allowed total debt to total capital ratio consistent with such allowed ratio under Dominion Energy’s joint revolving credit facility and can be used to support bank borrowings and the issuance of commercial paper.