Capitalization - Schedule of Long-Term Debt Maturities (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
2026	$ 250
2027	780
2028	800
2029	44
2030	635
Long-term debt, fair value	25,551	$ 24,651
Carrying Amount
Debt Instrument [Line Items]
Long-term debt, fair value	25,801	24,651
CECONY
Debt Instrument [Line Items]
2026	250
2027	700
2028	800
2029	0
2030	600
Long-term debt, fair value	24,060	23,409
CECONY | Carrying Amount
Debt Instrument [Line Items]
Long-term debt, fair value	$ 24,310	$ 23,409