XML 97 R83.htm IDEA: XBRL DOCUMENT v3.21.1
Derivatives and Hedge Accounting Activities (Selected Information Related to Losses on Cash Flow Hedges Included in AOCI) (Detail)
$ in Millions
3 Months Ended
Mar. 31, 2021
USD ($)
Derivative Instruments Gain Loss [Line Items]  
AOCI After-Tax $ (367)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax (40)
Virginia Electric and Power Company  
Derivative Instruments Gain Loss [Line Items]  
AOCI After-Tax (27)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax (2)
Interest rate  
Derivative Instruments Gain Loss [Line Items]  
AOCI After-Tax (367)
Interest rate, Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax $ (40)
Maximum Term 393 months
Interest rate | Virginia Electric and Power Company  
Derivative Instruments Gain Loss [Line Items]  
AOCI After-Tax $ (27)
Interest rate, Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax $ (2)
Maximum Term 393 months