XML 129 R116.htm IDEA: XBRL DOCUMENT v3.22.2
Credit Risk (Narrative) (Detail)
6 Months Ended
Jun. 30, 2022
USD ($)
counterparty
Dec. 31, 2021
USD ($)
Concentration Risk and Guarantor Obligations [Line Items]    
Credit exposure $ 156,000,000  
Additional collateral to be posted if the credit related contingent features were triggered 213,000,000 $ 31,000,000
Collateral derivatives with credit-related contingent provision in a liability position 3,000,000 66,000,000
Letter of credit as collateral posted for derivatives in liability position 68,000,000  
Aggregate fair value of all derivative instruments with credit contingent provisions that are in a liability position 216,000,000 97,000,000
Virginia Electric and Power Company    
Concentration Risk and Guarantor Obligations [Line Items]    
Credit exposure 25,000,000  
Additional collateral to be posted if the credit related contingent features were triggered 68,000,000 22,000,000
Collateral derivatives with credit-related contingent provision in a liability position   54,000,000
Letter of credit as collateral posted for derivatives in liability position 68,000,000  
Aggregate fair value of all derivative instruments with credit contingent provisions that are in a liability position $ 68,000,000 $ 76,000,000
Credit Concentration Risk    
Concentration Risk and Guarantor Obligations [Line Items]    
Number of counterparties | counterparty 0  
Amount of exposure for single counterparty $ 48,000,000  
Credit Concentration Risk | Wholesale Customers | Sales Revenue, Net | Virginia Electric and Power Company    
Concentration Risk and Guarantor Obligations [Line Items]    
Number of counterparties | counterparty 0  
Amount of exposure for single counterparty $ 6,000,000  
Credit Concentration Risk | Investment Grade | Investment Grade Counterparty    
Concentration Risk and Guarantor Obligations [Line Items]    
Concentration risk, percentage (percentage) 81.00%  
Credit Concentration Risk | Investment Grade | Investment Grade Counterparty | Virginia Electric and Power Company    
Concentration Risk and Guarantor Obligations [Line Items]    
Concentration risk, percentage (percentage) 50.00%