Regulatory Matters - Utility Rate Narrative and RECO Narrative (Details) $ in Thousands					1 Months Ended				23 Months Ended	36 Months Ended
	Jan. 01, 2024 USD ($)	Aug. 30, 2022 USD ($)	Jan. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)	Aug. 31, 2023 USD ($) substation	Apr. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jan. 31, 2022	Dec. 31, 2021	Dec. 31, 2025	Dec. 31, 2022	Dec. 31, 2023 USD ($)
CECONY
Public Utilities, General Disclosures [Line Items]
Number of substations | substation					2
Deferred costs												$ 3,000
CECONY | Electric
Public Utilities, General Disclosures [Line Items]
Authorized return on common equity (percent)											8.80%
Common equity ratio (percent)											48.00%
CECONY | Electric | Scenario, Forecast
Public Utilities, General Disclosures [Line Items]
Authorized return on common equity (percent)										925.00%
Common equity ratio (percent)										48.00%
RECO
Public Utilities, General Disclosures [Line Items]
Deferred costs												$ 4,800
Authorized return on common equity (percent)								9.60%	9.50%
Common equity ratio (percent)								48.51%	48.32%
RECO | New Jersey Board of Public Utilities
Public Utilities, General Disclosures [Line Items]
Investment plan							$ 47,800
Investment plan, term (in years)							5 years
RECO | Electric
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease), amount		$ 18,200		$ 16,900
RECO | Electric | Scenario, Forecast
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease), amount	$ 20,700
RECO | Electric | New Jersey Board of Public Utilities
Public Utilities, General Disclosures [Line Items]
Requested rate increase (decrease), amount			$ 9,650
Eastern Queens Reliability Project
Public Utilities, General Disclosures [Line Items]
Estimated cost of substations					$ 1,200,000
Brooklyn Clean Energy Hub
Public Utilities, General Disclosures [Line Items]
Estimated cost of substations						$ 810,000