exc-20201231
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imoreGasAndElectricCompanyMemberexc:UnderOverRecoveredTransmissionCostsMember2020-12-310001109357exc:PepcoHoldingsLLCMemberexc:UnderOverRecoveredTransmissionCostsMember2020-12-310001109357exc:UnderOverRecoveredTransmissionCostsMemberexc:PotomacElectricPowerCompanyMember2020-12-310001109357exc:UnderOverRecoveredTransmissionCostsMemberexc:DelmarvaPowerandLightCompanyMember2020-12-310001109357exc:UnderOverRecoveredTransmissionCostsMemberexc:AtlanticCityElectricCompanyMember2020-12-310001109357exc:RenewablePortfolioStandardsCostsMember2020-12-310001109357exc:RenewablePortfolioStandardsCostsMemberexc:CommonwealthEdisonCoMember2020-12-310001109357exc:RenewablePortfolioStandardsCostsMemberexc:PecoEnergyCoMember2020-12-310001109357exc:BaltimoreGasAndElectricCompanyMemberexc:RenewablePortfolioStandardsCostsMember2020-12-310001109357exc:RenewablePortfolioStandardsCostsMemberexc:PepcoHoldingsLLCMember2020-12-310001109357exc:RenewablePortfolioStandardsCostsMemberexc:PotomacElectricPowerCompanyMember2020-12-310001109357exc:RenewablePortfolioStandardsCostsMemberexc:DelmarvaPowerandLightCompanyMember2020-12-310001109357exc:RenewablePortfolioStandardsCostsMemberexc:AtlanticCityElectricCompanyMember2020-12-310001109357us-gaap:StrandedCostsMember2020-12-310001109357us-gaap:StrandedCostsMemberexc:CommonwealthEdisonCoMember2020-12-310001109357us-gaap:StrandedCostsMemberexc:PecoEnergyCoMember2020-12-310001109357exc:BaltimoreGasAndElectricCompanyMemberus-gaap:StrandedCostsMember2020-12-310001109357us-gaap:StrandedCostsMemberexc:PepcoHoldingsLLCMember2020-12-310001109357us-gaap:StrandedCostsMemberexc:PotomacElectricPowerCompanyMember2020-12-310001109357us-gaap:StrandedCostsMemberexc:DelmarvaPowerandLightCompanyMember2020-12-310001109357us-gaap:StrandedCostsMemberexc:AtlanticCityElectricCompanyMember2020-12-310001109357exc:RegulatoryLiabilitiesOtherMember2020-12-310001109357exc:RegulatoryLiabilitiesOtherMemberexc:CommonwealthEdisonCoMember2020-12-310001109357exc:RegulatoryLiabilitiesOtherMemberexc:PecoEnergyCoMember2020-12-310001109357exc:RegulatoryLiabilitiesOtherMemberexc:BaltimoreGasAndElectricCompanyMember2020-12-310001109357exc:RegulatoryLiabilitiesOtherMemberexc:PepcoHoldingsLLCMember2020-12-310001109357exc:RegulatoryLiabilitiesOtherMemberexc:PotomacElectricPowerCompanyMember2020-12-310001109357exc:RegulatoryLiabilitiesOtherMemberexc:DelmarvaPowerandLightCompanyMember2020-12-310001109357exc:RegulatoryLiabilitiesOtherMemberexc:AtlanticCityElectricCompanyMember2020-12-310001109357exc:RegulatoryAssets2019Member2020-01-012020-12-310001109357us-gaap:PensionAndOtherPostretirementPlansCostsMember2019-12-310001109357us-gaap:PensionAndOtherPostretirementPlansCostsMemberexc:CommonwealthEdisonCoMember2019-12-310001109357us-gaap:PensionAndOtherPostretirementPlansCostsMemberexc:PecoEnergyCoMember2019-12-310001109357exc:BaltimoreGasAndElectricCompanyMemberus-gaap:PensionAndOtherPostretirementPlansCostsMember2019-12-310001109357us-gaap:PensionAndOtherPostretirementPlansCostsMemberexc:PepcoHoldingsLLCMember2019-12-310001109357us-gaap:PensionAndOtherPostretirementPlansCostsMemberexc:PotomacElectricPowerCompanyMember2019-12-310001109357us-gaap:PensionAndOtherPostretirementPlansCostsMemberexc:DelmarvaPowerandLightCompanyMember2019-12-310001109357us-gaap:PensionAndOtherPostretirementPlansCostsMemberexc:AtlanticCityElectricCompanyMember2019-12-310001109357exc:PensionandPostRetirementPlanMergerCostsMember2019-12-310001109357exc:PensionandPostRetirementPlanMergerCostsMemberexc:CommonwealthEdisonCoMember2019-12-310001109357exc:PensionandPostRetirementPlanMergerCostsMemberexc:PecoEnergyCoMember2019-12-310001109357exc:PensionandPostRetirementPlanMergerCostsMemberexc:BaltimoreGasAndElectricCompanyMember2019-12-310001109357exc:PensionandPostRetirementPlanMergerCostsMemberexc:PepcoHoldingsLLCMember2019-12-310001109357exc:PensionandPostRetirementPlanMergerCostsMemberexc:PotomacElectricPowerCompanyMember2019-12-310001109357exc:PensionandPostRetirementPlanMergerCostsMemberexc:DelmarvaPowerandLightCompanyMember2019-12-310001109357exc:PensionandPostRetirementPlanMergerCostsMemberexc:AtlanticCityElectricCompanyMember2019-12-310001109357us-gaap:DeferredIncomeTaxChargesMember2019-12-310001109357us-gaap:DeferredIncomeTaxChargesMemberexc:CommonwealthEdisonCoMember2019-12-310001109357us-gaap:DeferredIncomeTaxChargesMemberexc:PecoEnergyCoMember2019-12-310001109357us-gaap:DeferredIncomeTaxChargesMemberexc:BaltimoreGasAndElectricCompanyMember2019-12-310001109357us-gaap:DeferredIncomeTaxChargesMemberexc:PepcoHoldingsLLCMember2019-12-310001109357us-gaap:DeferredIncomeTaxChargesMemberexc:PotomacElectricPowerCompanyMember2019-12-310001109357us-gaap:DeferredIncomeTaxChargesMemberexc:DelmarvaPowerandLightCompanyMember2019-12-310001109357us-gaap:DeferredIncomeTaxChargesMemberexc:AtlanticCityElectricCompanyMember2019-12-310001109357exc:AdvancedMeteringInfrastructureDeploymentCostsMember2019-12-310001109357exc:CommonwealthEdisonCoMemberexc:AdvancedMeteringInfrastructureDeploy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