2.2.0.7 true Regulatory Assets (net) (Details) (USD $) 4060 - Disclosure - Regulatory Assets (net) (Details) true false In Millions false false 1 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 $ false 2 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 $ false 3 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false ceg_RateStabilizationDeferralCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi ceg_RateStabilizationDeferralCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 4 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false ceg_RateStabilizationDeferralCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi ceg_RateStabilizationDeferralCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 5 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false ceg_RateStabilizationDeferralCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi ceg_RateStabilizationDeferralCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 6 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false ceg_OtherDeferredFuelCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi ceg_OtherDeferredFuelCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 7 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false ceg_OtherDeferredFuelCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi ceg_OtherDeferredFuelCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 8 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false ceg_ElectricGenerationRelatedRegulatoryAssetMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi ceg_ElectricGenerationRelatedRegulatoryAssetMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 9 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false ceg_ElectricGenerationRelatedRegulatoryAssetMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi ceg_ElectricGenerationRelatedRegulatoryAssetMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 10 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false us-gaap_AssetRetirementObligationCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_AssetRetirementObligationCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 11 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false us-gaap_AssetRetirementObligationCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_AssetRetirementObligationCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 12 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false us-gaap_DeferredIncomeTaxChargesMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_DeferredIncomeTaxChargesMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 13 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false us-gaap_DeferredIncomeTaxChargesMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_DeferredIncomeTaxChargesMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 14 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false us-gaap_DeferredProjectCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_DeferredProjectCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 15 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false us-gaap_DeferredProjectCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_DeferredProjectCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 16 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false ceg_PostRetirementAndPostEmploymentBenefitCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi ceg_PostRetirementAndPostEmploymentBenefitCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 17 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false ceg_PostRetirementAndPostEmploymentBenefitCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi ceg_PostRetirementAndPostEmploymentBenefitCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 18 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false us-gaap_EnvironmentalRestorationCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_EnvironmentalRestorationCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 $ false 19 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false us-gaap_EnvironmentalRestorationCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_EnvironmentalRestorationCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 20 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false ceg_WorkforceReductionCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi ceg_WorkforceReductionCostsMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 21 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false ceg_NetRegulatoryAssetsOtherMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi ceg_NetRegulatoryAssetsOtherMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 22 USD true false false false us-gaap_SubsidiariesMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SubsidiariesMember dei_LegalEntityAxis explicitMember false false ceg_NetRegulatoryAssetsOtherMember ceg_RegulatoryAssetsAndLiabilitiesAxis xbrldi http://xbrl.org/2006/xbrldi ceg_NetRegulatoryAssetsOtherMember ceg_RegulatoryAssetsAndLiabilitiesAxis explicitMember USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ 3 Regulatory assets & liabilities 1 ceg_RegulatoryAssetAndLiabiltiesLineItems ceg false na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:stringItemType string No definition available. false 4 Total regulatory assets (net) 2 us-gaap_NetRegulatoryAssets us-gaap true debit instant No definition available. false false false false false false false false false false false terselabel false 1 true true false false 486900000 486.9 true false false 2 true true false false 574400000 574.4 true false false 3 true true false false 477500000 477.5 true false false 4 true true false false 536300000 536.3 true false false 5 false false false false 0 0 true false false 6 true true false false 14300000 14.3 true false false 7 true true false false 24400000 24.4 true false false 8 true true false false 102500000 102.5 true false false 9 true true false false 118000000 118.0 true false false 10 true true false false -210100000 -210.1 true false false 11 true true false false -198000000 -198.0 true false false 12 true true false false 67600000 67.6 true false false 13 true true false false 63200000 63.2 true false false 14 true true false false 22100000 22.1 true false false 15 true true false false 15600000 15.6 true false false 16 true true false false 9600000 9.6 true false false 17 true true false false 12900000 12.9 true false false 18 true true false false 6500000 6.5 true false false 19 true true false false 7700000 7.7 true false false 20 true true false false 1500000 1.5 true false false 21 true true false false -4600000 -4.6 true false false 22 true true false false -5700000 -5.7 true false false xbrli:monetaryItemType monetary The net amount of all regulatory assets less all regulatory liabilities as of the end of the period No authoritative reference available. false 5 Less: Current portion of regulatory assets (net) 2 us-gaap_RegulatoryAssetsCurrent us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 72500000 72.5 true false false 2 false true false false 79700000 79.7 true false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:monetaryItemType monetary Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 71 -Paragraph 9, 10 false 6 Long-term portion of regulatory assets (net) 2 us-gaap_RegulatoryAssetsNoncurrent us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 414400000 414.4 true false false 2 false true false false 494700000 494.7 true false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:monetaryItemType monetary Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 71 -Paragraph 9, 10 false 7 Rate cap for BGE residential electric customers from July 1, 2006 until May 31, 2007 (in hundredths) 2 ceg_RateCapImposedOnPublicUtilitySubsidiary ceg false na instant This element represents the rate cap imposed on a public utility subsidiary of the reporting entity. false false false false false false false false false false false terselabel false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false true false false 0.15 0.15 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false us-types:percentItemType pure This element represents the rate cap imposed on a public utility subsidiary of the reporting entity. No authoritative reference available. false 8 Deferred expense related to electricity purchased for resale 2 us-gaap_DeferredPurchasedPowerCosts us-gaap true debit duration No definition available. false false false false false false false false false false false terselabel false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false true false false 306400000 306.4 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:monetaryItemType monetary Costs of power used for operations in prior periods that were expected to be recovered from customers in future periods. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 9 Recovered portion of regulatory assets 2 us-gaap_AmortizationOfRegulatoryAsset us-gaap true debit duration No definition available. false false false false false false false false false false false terselabel false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false true false false 51400000 51.4 true false false 4 false true false false 57100000 57.1 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:monetaryItemType monetary The expense charged against earnings during the period to allocate the capitalized costs of regulatory assets over the periods expected to benefit from such costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 10 Maximum term of amortizing the rate stabilization deferral into earnings (in years) 2 ceg_AmortizationTermOfRateStabilizationPlanRegulatoryAssetMaximumYears ceg false na duration This element represents the maximum term over which the rate stabilization deferral is to be amortized into earnings, in... false false false false false false false false false false false terselabel false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false true false false 10 10 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:integerItemType integer This element represents the maximum term over which the rate stabilization deferral is to be amortized into earnings, in years. No authoritative reference available. false 11 Term of recovery from customers that participated in the deferral from June 1, 2007 to December 31, 2007 (in months) 2 ceg_TermOfRecoveriesOfDeferralsFromCustomerForSpecifiedPeriod ceg false na duration This element represents the recovery term of deferred expenses from customers over the specified period, in months. false false false false false false false false false false false terselabel false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false true false false 21 21 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:integerItemType integer This element represents the recovery term of deferred expenses from customers over the specified period, in months. No authoritative reference available. false 12 Amortization period of deferred costs (in years) 2 us-gaap_RegulatoryNoncurrentAssetAmortizationPeriod us-gaap true na duration No definition available. false false false false false false false false false false false terselabel false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 5 5 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 15 15 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 5 5 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:stringItemType string The amortization period for recovery of the individual regulatory noncurrent asset in a schedule of regulatory noncurrent assets Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 71 -Paragraph 9, 10 false 13 Portion of electric generation-related regulatory asset representing income taxes recoverable that do not earn a regulated rate of return 2 ceg_IncomeTaxRecoverableRegulatoryAssets ceg false debit instant This element represents the portion of regulatory asset that represents income taxes recoverable through future rates that do... false false false false false false false false false false false terselabel false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false true false false 62800000 62.8 true false false 9 false true false false 72400000 72.4 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:monetaryItemType monetary This element represents the portion of regulatory asset that represents income taxes recoverable through future rates that do not earn a regular rate of return. No authoritative reference available. false 14 Rate relief for clean-up costs applied for and received 2 ceg_ReceivedRateReliefEnvironmentalCleanUpCostsIncurredPriorToTenYears ceg false credit duration This element represents the clean up costs related to deferred environmental costs that were applied for and received by the... false false false false false false false false false false false terselabel false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false true false false 5400000 5.4 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:monetaryItemType monetary This element represents the clean up costs related to deferred environmental costs that were applied for and received by the reporting entity. No authoritative reference available. false 15 Amortization of deferred environmental costs incurred through October 1995 2 ceg_AggregateAmountOfAmortizedDeferredEnvironmentalCostsIncurredBeforeFourteenYears ceg false debit instant This element represents the amortized portion of deferred environmental costs that were incurred prior to October 1995. false false false false false false false false false false false terselabel false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false true false false 21600000 21.6 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:monetaryItemType monetary This element represents the amortized portion of deferred environmental costs that were incurred prior to October 1995. No authoritative reference available. false 16 Amount of deferred environmental costs incurred from November 1995 through June 2000 being amortized 2 ceg_AggregateAmountOfCapitalizedDeferredEnvironmentalCostsIncurredBeforeTenYears ceg false debit instant This element represents the deferred environmental costs incurred from November 1995 through June 2000. false false false false false false false false false false false terselabel false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 true true false false 6400000 6.4 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:monetaryItemType monetary This element represents the deferred environmental costs incurred from November 1995 through June 2000. No authoritative reference available. false 17 Amortization term for deferred environmental costs incurred through June 2000 (in years) 2 ceg_TermOfAmortizingDeferredEnvironmentalCostsIncurredThroughJune2000Years ceg false na duration This element represents the term over which the deferred environmental costs that were incurred through June 2000 are to be... false false false false false false false false false false false terselabel false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false true false false 10 10 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:integerItemType integer This element represents the term over which the deferred environmental costs that were incurred through June 2000 are to be amortized, in years. No authoritative reference available. false 18 Amortization term for deferred environmental costs incurred from July 2000 through November 2005 (in years) 2 ceg_TermOfAmortizingDeferredEnvironmentalCostsIncurredFromJuly2000ThroughNovember2005Years ceg false na duration This element represents the term over which the deferred environmental costs that were incurred from July 2000 through... false false false false false false false false false false false terselabel false 1 false false false false 0 0 true false false 2 false false false false 0 0 true false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false true false false 10 10 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false xbrli:integerItemType integer This element represents the term over which the deferred environmental costs that were incurred from July 2000 through November 2005 are to be amortized, in years. No authoritative reference available. false 22 16 false HundredThousands UnKnown UnKnown false true