XML 107 R61.htm IDEA: XBRL DOCUMENT
v3.20.1

Environmental Matters - Additional Information (Details) - USD ($) $ in Billions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Dec. 31, 2019
CECONY | Asbestos Proceedings |  |
Site Contingency [Line Items] |  |
Estimated undiscounted asbestos liability (years) | 15 years |
Superfund Sites | Manufactured Gas Plant Sites | Maximum |  |
Site Contingency [Line Items] |  |
Estimated aggregate undiscounted potential liability related environmental contaminants (up to) |  | $ 2.8
Superfund Sites | Manufactured Gas Plant Sites | Maximum | CECONY |  |
Site Contingency [Line Items] |  |
Estimated aggregate undiscounted potential liability related environmental contaminants (up to) |  | $ 2.6

X
- Definition Estimated Undiscounted Asbestos Liability In Year + References No definition available. + Details
Name: | ed_EstimatedUndiscountedAsbestosLiabilityInYear
Namespace Prefix: | ed_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Potential undiscounted liability for environmental loss contingencies gross. + References No definition available. + Details
Name: | ed_PotentialUndiscountedLiabilityForEnvironmentalLossContingenciesGross
Namespace Prefix: | ed_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_SiteContingencyLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=ed_ConsolidatedEdisonCompanyofNewYorkInc.Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LiabilityForCatastropheClaimsByCatastrophicEventAxis=ed_AsbestosRelatedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_EnvironmentalRemediationSiteAxis=ed_SuperfundSitesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=us-gaap_NaturalGasProcessingPlantMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |