Environmental Matters - Accrued Liabilities and Regulatory Assets (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Site Contingency [Line Items]
Accrued Liabilities	$ 1,037	$ 1,118
Regulatory assets	5,664	4,888
Manufactured gas plant sites
Site Contingency [Line Items]
Accrued Liabilities	941	1,016
Other Superfund Sites
Site Contingency [Line Items]
Accrued Liabilities	96	102
Superfund Sites
Site Contingency [Line Items]
Accrued Liabilities	1,037	1,118
Regulatory assets	1,038	1,105
CECONY
Site Contingency [Line Items]
Accrued Liabilities	942	1,026
CECONY | Manufactured gas plant sites
Site Contingency [Line Items]
Accrued Liabilities	846	924
CECONY | Other Superfund Sites
Site Contingency [Line Items]
Accrued Liabilities	96	102
CECONY | Superfund Sites
Site Contingency [Line Items]
Accrued Liabilities	942	1,026
Regulatory assets	$ 952	$ 1,022