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No authoritative reference available. false 116 Baltimore Gas and Electric Company | 6.99%, 1995 Series preference stock 0 na true na na No definition available. false true false false false false false false false false false http://www.constellation.com/role/disclosurecapitalizationdetails2 false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 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_SeriesCPreferredStockMember us-gaap_StatementClassOfStockAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SeriesCPreferredStockMember us-gaap_StatementClassOfStockAxis explicitMember Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 USDPerShare Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 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_SeriesCPreferredStockMember us-gaap_StatementClassOfStockAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_SeriesCPreferredStockMember us-gaap_StatementClassOfStockAxis explicitMember Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 USDPerShare Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. No authoritative reference available. false 119 BGE Preference Stock 2 ceg_SubsidaryPreferenceStockAbstract 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 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 121 Preferred stock dividend rate (in hundredths) 2 ceg_PreferredStockDividendRatePercentage ceg false na instant The percentage rate used to calculate dividend payments on preferred stock. false false false false false false false false false false false terselabel false 1 false true false false 0.0699 0.0699 false false false 2 false true false false 0.0699 0.0699 false false false us-types:percentItemType pure The percentage rate used to calculate dividend payments on preferred stock. 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No authoritative reference available. false 139 BGE Capital Trust II 0 na true na na No definition available. false true false false false false false false false false false http://www.constellation.com/role/disclosurecapitalizationdetails2 false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false false 15 USD true false false false ceg_BGECapitalTrustIIMember dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi ceg_BGECapitalTrustIIMember dei_LegalEntityAxis explicitMember Pure Standard http://www.xbrl.org/2003/instance pure xbrli 0 USDPerShare Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ na No definition available. No authoritative reference available. false 142 BGE Preference Stock 2 ceg_SubsidaryPreferenceStockAbstract 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 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 144 Preferred stock dividend rate (in hundredths) 2 ceg_PreferredStockDividendRatePercentage ceg false na instant The percentage rate used to calculate dividend payments on preferred stock. false false false false false false false false false false false terselabel false 1 false true false false 0.0620 0.0620 false false false 2 false false false false 0 0 false false false us-types:percentItemType pure The percentage rate used to calculate dividend payments on preferred stock. 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