v3.26.3
Property, Plant and Equipment (Narrative) (Detail)
 1 Months Ended 3 Months Ended 9 Months Ended 12 Months Ended
Jul. 31, 2026
USD ($)
Apr. 30, 2026
USD ($)
Jan. 31, 2026
USD ($)
Sep. 30, 2026
USD ($)
Mar. 31, 2026
USD ($)
Sep. 30, 2025
USD ($)
Sep. 30, 2026
USD ($)
Sep. 30, 2025
USD ($)
Dec. 31, 2025
USD ($)
GW
May 31, 2026
USD ($)
Oct. 31, 2024
Property, Plant, and Equipment [Line Items]                      
Noncontrolling Interests       $ 114,000,000 [1]   $ 22,000,000 [1] $ 267,000,000 [2] $ 122,000,000 [2]      
Income tax expense (benefit)       215,000,000 [3]   216,000,000 [3] 385,000,000 [4],[5] 476,000,000 [4]      
Virginia Electric and Power Company                      
Property, Plant, and Equipment [Line Items]                      
Excepted total project cost decrease     $ 400,000,000                
Excepted total project cost increase     $ 400,000,000                
Increase in estimated project cost $ 300,000,000                    
Approximate tariffs cost on equipment expected to be delivered             200,000,000        
Noncontrolling Interests       114,000,000 [6]   22,000,000 [6] 267,000,000 [7] 122,000,000 [7]      
Income tax expense (benefit)       220,000,000 [8]   151,000,000 [8] 519,000,000 [5],[9] 356,000,000 [9]      
Virginia Electric and Power Company | End of 2027                      
Property, Plant, and Equipment [Line Items]                      
Increase in estimated project cost             200,000,000        
Virginia Electric and Power Company | CVOW Commercial Project                      
Property, Plant, and Equipment [Line Items]                      
Charge (benefit) for costs not expected to be recovered including noncontrolling portion       $ 0   128,000,000 129,000,000 224,000,000      
Noncontrolling Interests           64,000,000 64,000,000 112,000,000      
Income tax expense (benefit)           $ (16,000,000) $ (17,000,000) $ (28,000,000)      
Ownership percentage       50.00%     50.00%       50.00%
Percentage of remaining construction costs, including contingency       8.00%     8.00%        
Virginia Electric and Power Company | CVOW Commercial Project | End of 2027                      
Property, Plant, and Equipment [Line Items]                      
Targeted capacity provided by legislation | GW                 2.6    
Anticipated projected cost                 $ 11,700,000,000    
Anticipated project cost contingency                 $ 100,000,000    
Nonregulated Renewable Natural Gas Facilities [Member] | Level 3                      
Property, Plant, and Equipment [Line Items]                      
Long-lived assets, estimated fair value       $ 468,000,000     $ 468,000,000        
Nonregulated Renewable Natural Gas Facilities [Member] | Location, Statement of Income, Balance [Axis]: d:ImpairmentOfAssetsAndOtherChargesBenefits                      
Property, Plant, and Equipment [Line Items]                      
Impairment of assets and other charges             820,000,000        
Asset impairment charges after tax             640,000,000        
Nonregulated Solar Generation Facilities                      
Property, Plant, and Equipment [Line Items]                      
Long lived asset held for sale       $ 262,000,000     $ 262,000,000        
Nonregulated Solar Generation Facilities | Location, Statement of Income, Balance [Axis]: d:ImpairmentOfAssetsAndOtherChargesBenefits                      
Property, Plant, and Equipment [Line Items]                      
Impairment of assets and other charges         $ 78,000,000            
Asset impairment charges after tax         60,000,000            
Nonregulated Solar Generation Facilities | Other Sales                      
Property, Plant, and Equipment [Line Items]                      
Disposal group, cash consideration                   $ 140,000,000  
Minimum | Virginia Electric and Power Company                      
Property, Plant, and Equipment [Line Items]                      
Increase in estimated project cost   $ 100,000,000                  
Minimum | Nonregulated Solar Generation Facilities | Level 3                      
Property, Plant, and Equipment [Line Items]                      
Long-lived assets, estimated fair value         $ 500,000,000            
[1] Items designated are other segment items for each reportable segment.
[2] Items designated are other segment items for each reportable segment.
[3] The significant expense categories and amounts in the segment information presented above align with the segment-level information that is regularly provided to Dominion Energy’s CODM.
[4] The significant expense categories and amounts in the segment information presented above align with the segment-level information that is regularly provided to Dominion Energy’s CODM.
[5] The Companies had no adjustments related to the following disclosure categories: foreign tax effects, effects of changes in tax law or rates enacted in the current period and effects of cross-border tax laws.
[6] Items designated are other segment items for each reportable segment.
[7] Items designated are other segment items for each reportable segment.
[8] The significant expense categories and amounts in the segment information presented above align with the segment-level information that is regularly provided to Virginia Power’s CODM.
[9] The significant expense categories and amounts in the segment information presented above align with the segment-level information that is regularly provided to Virginia Power’s CODM.