v3.26.1
Significant Financing Transactions (Commercial Paper, Bank Loans and Letters of Credit Outstanding) (Parenthetical) (Detail) - USD ($)
Jun. 30, 2026
Mar. 31, 2023
Line of Credit Facility [Line Items]    
Facility Limit $ 8,000,000,000  
Virginia Electric and Power Company    
Line of Credit Facility [Line Items]    
Facility Limit [1] 7,000,000,000  
Letter of Credit Matures in April 2032    
Line of Credit Facility [Line Items]    
Facility Limit 3,000,000,000  
Letter of Credit Matures in April 2032 | Virginia Electric and Power Company    
Line of Credit Facility [Line Items]    
Facility Limit 4,000,000,000  
Letter of Credit    
Line of Credit Facility [Line Items]    
Facility Limit   $ 100,000,000
Letter of Credit | Virginia Electric and Power Company    
Line of Credit Facility [Line Items]    
Facility Limit 450,000,000  
Letter of Credit | Virginia Electric and Power Company | Maximum    
Line of Credit Facility [Line Items]    
Facility Limit $ 3,000,000,000  
[1] 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 June 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.