Derivative Instruments and Hedging Activities - Hedged Volume of Derivative Transactions (Details)	Jun. 30, 2023 MWh gal MW MMBTU
Electric Energy (MWh)
Derivatives, Fair Value [Line Items]
Notional amount | MWh	27,335,565
Capacity (MW)
Derivatives, Fair Value [Line Items]
Notional amount | MW	44,400
Natural Gas (Dt)
Derivatives, Fair Value [Line Items]
Notional amount | MMBTU	313,190,000
Refined Fuels (gallons)
Derivatives, Fair Value [Line Items]
Notional amount | gal	3,276,000
CECONY | Electric Energy (MWh) | Subsidiaries
Derivatives, Fair Value [Line Items]
Notional amount | MWh	25,782,725
CECONY | Capacity (MW) | Subsidiaries
Derivatives, Fair Value [Line Items]
Notional amount | MW	38,100
CECONY | Natural Gas (Dt) | Subsidiaries
Derivatives, Fair Value [Line Items]
Notional amount | MMBTU	297,590,000
CECONY | Refined Fuels (gallons) | Subsidiaries
Derivatives, Fair Value [Line Items]
Notional amount | gal	3,276,000