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No authoritative reference available. false 3 Interest rate 2 us-gaap_NotionalAmountOfInterestRateDerivatives us-gaap true debit instant No definition available. false false false false false false false false false false false false 1 true true false false 75000000 75000000 false false false xbrli:monetaryItemType monetary Aggregate notional amount of interest rate derivatives, which relates to the currency amount specified in the interest rate derivative instruments. No authoritative reference available. false 4 Current Derivative Contract | Natural Gas | Fixed Price 0 na true na na No definition available. false true false false false false false false false false false http://www.dom.com/taxonomy/role/disclosurevolumeofourderivativeactivity false 1 false false false false 0 0 false false false false 2 true false false false Current Derivative Contract us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis xbrldi http://xbrl.org/2006/xbrldi d_CurrentDerivativeContractMember us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis explicitMember false false Natural Gas d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis xbrldi http://xbrl.org/2006/xbrldi d_NaturalGasMember d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis explicitMember false false Fixed Price d_DerivativesByDerivativeInstrumentContractAxis xbrldi http://xbrl.org/2006/xbrldi d_FixedPriceMember d_DerivativesByDerivativeInstrumentContractAxis explicitMember pure Standard http://www.xbrl.org/2003/instance pure 0 na No definition available. No authoritative reference available. false 5 Volume of open derivative positions 2 us-gaap_DerivativeNumberOfInstrumentsHeld us-gaap true na instant No definition available. false false false false false false false false false false false false 1 false true false false 516 516 [1] false false false xbrli:integerItemType integer The number of derivative instruments of a particular group held by the entity. 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No authoritative reference available. false 8 Volume of open derivative positions 2 us-gaap_DerivativeNumberOfInstrumentsHeld us-gaap true na instant No definition available. false false false false false false false false false false false false 1 false true false false 1107 1107 [1] false false false xbrli:integerItemType integer The number of derivative instruments of a particular group held by the entity. No authoritative reference available. false 10 Current Derivative Contract | Electricity | Fixed Price 0 na true na na No definition available. false true false false false false false false false false false http://www.dom.com/taxonomy/role/disclosurevolumeofourderivativeactivity false 1 false false false false 0 0 false false false false 4 true false false false Current Derivative Contract us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis xbrldi http://xbrl.org/2006/xbrldi d_CurrentDerivativeContractMember us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis explicitMember false false Electricity d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis xbrldi http://xbrl.org/2006/xbrldi d_ElectricityMember d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis explicitMember false false Fixed Price d_DerivativesByDerivativeInstrumentContractAxis xbrldi http://xbrl.org/2006/xbrldi d_FixedPriceMember d_DerivativesByDerivativeInstrumentContractAxis explicitMember pure Standard http://www.xbrl.org/2003/instance pure 0 na No definition available. No authoritative reference available. false 11 Volume of open derivative positions 2 us-gaap_DerivativeNumberOfInstrumentsHeld us-gaap true na instant No definition available. false false false false false false false false false false false false 1 false true false false 22096134 22096134 [2] false false false xbrli:integerItemType integer The number of derivative instruments of a particular group held by the entity. No authoritative reference available. false 13 Current Derivative Contract | Electricity | Financial Transmission Rights 0 na true na na No definition available. false true false false false false false false false false false http://www.dom.com/taxonomy/role/disclosurevolumeofourderivativeactivity false 1 false false false false 0 0 false false false false 5 true false false false Current Derivative Contract us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis xbrldi http://xbrl.org/2006/xbrldi d_CurrentDerivativeContractMember us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis explicitMember false false Electricity d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis xbrldi http://xbrl.org/2006/xbrldi d_ElectricityMember d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis explicitMember false false Financial Transmission Rights d_DerivativesByDerivativeInstrumentContractAxis xbrldi http://xbrl.org/2006/xbrldi d_FinancialTransmissionRightsMember d_DerivativesByDerivativeInstrumentContractAxis explicitMember pure Standard http://www.xbrl.org/2003/instance pure 0 na No definition available. No authoritative reference available. false 14 Volume of open derivative positions 2 us-gaap_DerivativeNumberOfInstrumentsHeld us-gaap true na instant No definition available. false false false false false false false false false false false false 1 false true false false 76735785 76735785 false false false xbrli:integerItemType integer The number of derivative instruments of a particular group held by the entity. No authoritative reference available. false 16 Current Derivative Contract | Capacity 0 na true na na No definition available. false true false false false false false false false false false http://www.dom.com/taxonomy/role/disclosurevolumeofourderivativeactivity false 1 false false false false 0 0 false false false false 6 true false false false Current Derivative Contract us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis xbrldi http://xbrl.org/2006/xbrldi d_CurrentDerivativeContractMember us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis explicitMember false false Capacity d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis xbrldi http://xbrl.org/2006/xbrldi d_CapacityMember d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis explicitMember pure Standard http://www.xbrl.org/2003/instance pure 0 na No definition available. No authoritative reference available. false 17 Volume of open derivative positions 2 us-gaap_DerivativeNumberOfInstrumentsHeld us-gaap true na instant No definition available. false false false false false false false false false false false false 1 false true false false 1448200 1448200 false false false xbrli:integerItemType integer The number of derivative instruments of a particular group held by the entity. 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No authoritative reference available. false 20 Volume of open derivative positions 2 us-gaap_DerivativeNumberOfInstrumentsHeld us-gaap true na instant No definition available. false false false false false false false false false false false false 1 false true false false 149184000 149184000 [3] false false false xbrli:integerItemType integer The number of derivative instruments of a particular group held by the entity. 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No authoritative reference available. false 25 Noncurrent Derivative Contract | Natural Gas | Fixed Price 0 na true na na No definition available. false true false false false false false false false false false http://www.dom.com/taxonomy/role/disclosurevolumeofourderivativeactivity false 1 false false false false 0 0 false false false false 9 true false false false Noncurrent Derivative Contract us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis xbrldi http://xbrl.org/2006/xbrldi d_NoncurrentDerivativeContractMember us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis explicitMember false false Natural Gas d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis xbrldi http://xbrl.org/2006/xbrldi d_NaturalGasMember d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis explicitMember false false Fixed Price d_DerivativesByDerivativeInstrumentContractAxis xbrldi http://xbrl.org/2006/xbrldi d_FixedPriceMember d_DerivativesByDerivativeInstrumentContractAxis explicitMember pure Standard http://www.xbrl.org/2003/instance pure 0 na No definition available. No authoritative reference available. false 26 Volume of open derivative positions 2 us-gaap_DerivativeNumberOfInstrumentsHeld us-gaap true na instant No definition available. false false false false false false false false false false false false 1 false true false false 116 116 [1] false false false xbrli:integerItemType integer The number of derivative instruments of a particular group held by the entity. No authoritative reference available. false 28 Noncurrent Derivative Contract | Natural Gas | Basis 0 na true na na No definition available. false true false false false false false false false false false http://www.dom.com/taxonomy/role/disclosurevolumeofourderivativeactivity false 1 false false false false 0 0 false false false false 10 true false false false Noncurrent Derivative Contract us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis xbrldi http://xbrl.org/2006/xbrldi d_NoncurrentDerivativeContractMember us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis explicitMember false false Natural Gas d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis xbrldi http://xbrl.org/2006/xbrldi d_NaturalGasMember d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis explicitMember false false Basis d_DerivativesByDerivativeInstrumentContractAxis xbrldi http://xbrl.org/2006/xbrldi d_BasisMember d_DerivativesByDerivativeInstrumentContractAxis explicitMember pure Standard http://www.xbrl.org/2003/instance pure 0 na No definition available. No authoritative reference available. false 29 Volume of open derivative positions 2 us-gaap_DerivativeNumberOfInstrumentsHeld us-gaap true na instant No definition available. false false false false false false false false false false false false 1 false true false false 522 522 [1] false false false xbrli:integerItemType integer The number of derivative instruments of a particular group held by the entity. No authoritative reference available. false 31 Noncurrent Derivative Contract | Electricity | Fixed Price 0 na true na na No definition available. false true false false false false false false false false false http://www.dom.com/taxonomy/role/disclosurevolumeofourderivativeactivity false 1 false false false false 0 0 false false false false 11 true false false false Noncurrent Derivative Contract us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis xbrldi http://xbrl.org/2006/xbrldi d_NoncurrentDerivativeContractMember us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis explicitMember false false Electricity d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis xbrldi http://xbrl.org/2006/xbrldi d_ElectricityMember d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis explicitMember false false Fixed Price d_DerivativesByDerivativeInstrumentContractAxis xbrldi http://xbrl.org/2006/xbrldi d_FixedPriceMember d_DerivativesByDerivativeInstrumentContractAxis explicitMember pure Standard http://www.xbrl.org/2003/instance pure 0 na No definition available. No authoritative reference available. false 32 Volume of open derivative positions 2 us-gaap_DerivativeNumberOfInstrumentsHeld us-gaap true na instant No definition available. false false false false false false false false false false false false 1 false true false false 9608229 9608229 [2] false false false xbrli:integerItemType integer The number of derivative instruments of a particular group held by the entity. No authoritative reference available. false 34 Noncurrent Derivative Contract | Electricity | Financial Transmission Rights 0 na true na na No definition available. false true false false false false false false false false false http://www.dom.com/taxonomy/role/disclosurevolumeofourderivativeactivity false 1 false false false false 0 0 false false false false 12 true false false false Noncurrent Derivative Contract us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis xbrldi http://xbrl.org/2006/xbrldi d_NoncurrentDerivativeContractMember us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis explicitMember false false Electricity d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis xbrldi http://xbrl.org/2006/xbrldi d_ElectricityMember d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis explicitMember false false Financial Transmission Rights d_DerivativesByDerivativeInstrumentContractAxis xbrldi http://xbrl.org/2006/xbrldi d_FinancialTransmissionRightsMember d_DerivativesByDerivativeInstrumentContractAxis explicitMember pure Standard http://www.xbrl.org/2003/instance pure 0 na No definition available. No authoritative reference available. false 35 Volume of open derivative positions 2 us-gaap_DerivativeNumberOfInstrumentsHeld us-gaap true na instant No definition available. false false false false false false false false false false false false 1 false true false false 2208448 2208448 false false false xbrli:integerItemType integer The number of derivative instruments of a particular group held by the entity. No authoritative reference available. false 37 Noncurrent Derivative Contract | Capacity 0 na true na na No definition available. false true false false false false false false false false false http://www.dom.com/taxonomy/role/disclosurevolumeofourderivativeactivity false 1 false false false false 0 0 false false false false 13 true false false false Noncurrent Derivative Contract us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis xbrldi http://xbrl.org/2006/xbrldi d_NoncurrentDerivativeContractMember us-gaap_DerivativeInstrumentsGainLossByDerivativeInstrumentRiskAxis explicitMember false false Capacity d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis xbrldi http://xbrl.org/2006/xbrldi d_CapacityMember d_DerivativeInstrumentsRelatedToOilAndGasProductionComponentsAxis explicitMember pure Standard http://www.xbrl.org/2003/instance pure 0 na No definition available. No authoritative reference available. false 38 Volume of open derivative positions 2 us-gaap_DerivativeNumberOfInstrumentsHeld us-gaap true na instant No definition available. false false false false false false false false false false false false 1 false true false false 4339950 4339950 false false false xbrli:integerItemType integer The number of derivative instruments of a particular group held by the entity. 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No authoritative reference available. false 41 Volume of open derivative positions 2 us-gaap_DerivativeNumberOfInstrumentsHeld us-gaap true na instant No definition available. false false false false false false false false false false false false 1 false true false false 380772000 380772000 [3] false false false xbrli:integerItemType integer The number of derivative instruments of a particular group held by the entity. No authoritative reference available. false 1 Includes options. 2 Includes power options. 3 Includes NGL and oil derivatives. 1 28 false NoRounding UnKnown UnKnown false true