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Derivatives and Hedge Accounting Activities (Selected Information Related to Gains (Losses) on Cash Flow Hedges Included in AOCI) (Detail) $ in Millions | 12 Months Ended
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Dec. 31, 2020 USD ($)
Derivative Instruments Gain Loss [Line Items] |
AOCI After-Tax | $ (419)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax | (43)
Virginia Electric and Power Company |
Derivative Instruments Gain Loss [Line Items] |
AOCI After-Tax | (60)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax | (2)
Commodity | Natural Gas |
Derivative Instruments Gain Loss [Line Items] |
AOCI After-Tax | (1)
Commodities, Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax | $ (1)
Maximum Term | 12 months
Interest rate |
Derivative Instruments Gain Loss [Line Items] |
AOCI After-Tax | $ (418)
Interest rate, Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax | $ (42)
Maximum Term | 396 months
Interest rate | Virginia Electric and Power Company |
Derivative Instruments Gain Loss [Line Items] |
AOCI After-Tax | $ (60)
Interest rate, Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax | $ (2)
Maximum Term | 396 months

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- Definition Accumulated change, net of tax, in accumulated gains and losses from instruments designated and qualifying as the effective portion of cash flow hedges that will be reclassified into earnings during the next 12 months. + References No definition available. + Details
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- Definition Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e637-108580 + Details
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- Definition The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994 + Details
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- Definition Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994 + Details
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- Definition The estimated net amount of unrealized gains or losses on price risk cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994 + Details
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