2.2.0.7 true Financial Information by Business Segment (Financial data for the business segments) (Details) (USD $) 41001 - Disclosure - Financial Information by Business Segment (Financial data for the business segments) (Details) true false In Millions false false 1 USD true false false false CONSOLIDATED EDISON INC [Member] dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_ParentCompanyMember dei_LegalEntityAxis explicitMember Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Unit1 Standard http://www.xbrl.org/2003/instance shares xbrli 0 Unit14 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 $ false 2 USD true false false false CONSOLIDATED EDISON INC [Member] dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_ParentCompanyMember dei_LegalEntityAxis explicitMember Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Unit14 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Unit1 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 3 USD true false false false CONSOLIDATED EDISON INC [Member] dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_ParentCompanyMember dei_LegalEntityAxis explicitMember Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Unit14 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Unit1 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 4 USD true false false false CONSOLIDATED EDISON INC [Member] dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_ParentCompanyMember dei_LegalEntityAxis explicitMember Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Unit14 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Unit1 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ 1 CONSOLIDATED EDISON INC [Member] 0 na true na na No definition available. false true false false false false false false false false false http://www.coned.com/taxonomy/role/disclosurefinancialinformationbybusinesssegmentfinancialdataforbusinesssegmentsdetails false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false false 1 USD true false false false CONSOLIDATED EDISON INC [Member] dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_ParentCompanyMember dei_LegalEntityAxis explicitMember Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Unit1 Standard http://www.xbrl.org/2003/instance shares xbrli 0 Unit14 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 $ false 2 USD true false false false CONSOLIDATED EDISON INC [Member] dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_ParentCompanyMember dei_LegalEntityAxis explicitMember Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Unit14 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Unit1 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 3 USD true false false false CONSOLIDATED EDISON INC [Member] dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_ParentCompanyMember dei_LegalEntityAxis explicitMember Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Unit14 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Unit1 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 4 USD true false false false CONSOLIDATED EDISON INC [Member] dei_LegalEntityAxis xbrldi http://xbrl.org/2006/xbrldi us-gaap_ParentCompanyMember dei_LegalEntityAxis explicitMember Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Unit14 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Unit1 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ na No definition available. 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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 32 -Subparagraph b false 21 CECONY - Steam [Member] 0 na true na na No definition available. false true false false false false false false false false false http://www.coned.com/taxonomy/role/disclosurefinancialinformationbybusinesssegmentfinancialdataforbusinesssegmentsdetails false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false false 17 USD true false false false CECONY - Steam [Member] us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi ed_CeconySteamMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 18 USD true false false false CECONY - Steam [Member] us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi ed_CeconySteamMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 19 USD true false false false CECONY - Steam [Member] us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi ed_CeconySteamMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ false 20 USD true false false false CECONY - Steam [Member] us-gaap_SegmentReportingInformationBySegmentAxis xbrldi http://xbrl.org/2006/xbrldi ed_CeconySteamMember us-gaap_SegmentReportingInformationBySegmentAxis explicitMember Unit12 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 $ na No definition available. 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