v3.26.1
Commitments and Contingencies (Narrative) (Detail)
1 Months Ended 6 Months Ended 12 Months Ended
May 31, 2024
Oct. 31, 2020
Apr. 30, 2017
Petition
Aug. 31, 2016
T
Jun. 30, 2026
USD ($)
Facility
Site
Indicator
gal
Dec. 31, 2025
USD ($)
May 31, 2026
USD ($)
Apr. 30, 2026
USD ($)
Feb. 28, 2026
USD ($)
Mar. 31, 2023
USD ($)
Loss Contingencies [Line Items]                    
Revolving credit facility maximum borrowing capacity         $ 8,000,000,000          
Revolving Credit Facility                    
Loss Contingencies [Line Items]                    
Revolving credit facility maximum borrowing capacity               $ 7,000,000,000    
Letter of Credit                    
Loss Contingencies [Line Items]                    
Revolving credit facility maximum borrowing capacity                   $ 100,000,000
Sustainability Revolving Credit Facility                    
Loss Contingencies [Line Items]                    
Revolving credit facility maximum borrowing capacity             $ 500,000,000   $ 500,000,000  
Virginia Electric and Power Company                    
Loss Contingencies [Line Items]                    
Revolving credit facility maximum borrowing capacity [1]         7,000,000,000          
Virginia Electric and Power Company | Letter of Credit                    
Loss Contingencies [Line Items]                    
Revolving credit facility maximum borrowing capacity         450,000,000          
Virginia Electric and Power Company | Maximum | Letter of Credit                    
Loss Contingencies [Line Items]                    
Revolving credit facility maximum borrowing capacity         $ 3,000,000,000          
Virginia Electric and Power Company | EPA and State Regulatory Agencies                    
Loss Contingencies [Line Items]                    
Number of facilities to assess the applicability of section 316(b) | Facility         3          
Hydroelectric Facilities | EPA and State Regulatory Agencies                    
Loss Contingencies [Line Items]                    
Number of facilities to assess the applicability of section 316(b) | Facility         8          
Unfavorable Regulatory Action | EPA                    
Loss Contingencies [Line Items]                    
Electric generating station facilities water withdrawals per day | gal         2,000,000          
Electric generating station facilities heightened entrainment analysis per day | gal         125,000,000          
Valley Link Transmission Company, LLC [Member]                    
Loss Contingencies [Line Items]                    
Guarantee Obligation, Maximum Potential Loss Exposure, Outstanding Borrowings Limited Percentage           30.00%        
Valley Link Transmission Company, LLC [Member] | Revolving Credit Facility                    
Loss Contingencies [Line Items]                    
Guarantee Agreement, Financing Obligation           $ 180,000,000        
Credit facility, amount borrowed         $ 85,000,000 41,000,000        
Valley Link Transmission Company, LLC [Member] | Letter of Credit                    
Loss Contingencies [Line Items]                    
Guarantee Agreement, Financing Obligation           120,000,000        
Credit facility, amount borrowed         $ 90,000,000 90,000,000        
Carbon Regulations                    
Loss Contingencies [Line Items]                    
Public Utilities Significant Emission Rate Per Year CO2 Equivalent | T       75,000            
CWA | Unfavorable Regulatory Action                    
Loss Contingencies [Line Items]                    
Number of mandatory facility-specific factors | Indicator         5          
Number of optional facility-specific factors | Indicator         6          
Number of facilities that are subject to final regulations | Facility         14          
CWA | Unfavorable Regulatory Action | EPA | Final Rule to Revise Effluent Limitations Guidelines for Steam Electric Power Generating Category                    
Loss Contingencies [Line Items]                    
Number of separate petitions for reconsideration granted | Petition     2              
CWA | Unfavorable Regulatory Action | EPA | Minimum | Final Rule to Revise Effluent Limitations Guidelines for Steam Electric Power Generating Category                    
Loss Contingencies [Line Items]                    
Loss contingencies individual circumstances period 2029 2021                
CWA | Unfavorable Regulatory Action | EPA | Maximum | Final Rule to Revise Effluent Limitations Guidelines for Steam Electric Power Generating Category                    
Loss Contingencies [Line Items]                    
Loss contingencies individual circumstances period 2034 2028                
CWA | Unfavorable Regulatory Action | Virginia Electric and Power Company                    
Loss Contingencies [Line Items]                    
Number of facilities that are subject to final regulations | Facility         8          
Waste Management and Remediation | Unfavorable Regulatory Action | EPA                    
Loss Contingencies [Line Items]                    
Number of sites remediation work substantially completed | Site         4          
Number of additional sites which are not under investigation | Site         3          
Waste Management and Remediation | Unfavorable Regulatory Action | EPA | Former Gas Plant Site With Post Closure Groundwater Monitoring Program                    
Loss Contingencies [Line Items]                    
Environmental remediation reserves         $ 53,000,000 53,000,000        
Waste Management and Remediation | Unfavorable Regulatory Action | Virginia Electric and Power Company | EPA                    
Loss Contingencies [Line Items]                    
Number of sites with remediation plans | Site         1          
Number of additional sites which are not under investigation | Site         2          
Waste Management and Remediation | Unfavorable Regulatory Action | Virginia Electric and Power Company | EPA | Former Gas Plant Site With Post Closure Groundwater Monitoring Program                    
Loss Contingencies [Line Items]                    
Environmental remediation reserves         $ 48,000,000 $ 48,000,000        
[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.