Consolidated Statement of Capitalization - Long-term Debt (Parenthetical) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2024	Nov. 30, 2024	Dec. 31, 2023
Tax-Exempt Debt
Schedule of Capitalization, Long-term Debt [Line Items]
Long-Term Debt, Gross		$ 225		$ 450
Debenture Series 2017B, 4.825% Due 2027 | Debentures
Schedule of Capitalization, Long-term Debt [Line Items]
Debt instrument, SOFR variable rate		52.00%
Tax Exempt Debt Series 2010A Due 2024 | Tax-Exempt Debt
Schedule of Capitalization, Long-term Debt [Line Items]
Long-Term Debt, Gross	[1]	$ 0	$ 225	$ 225

[1] In November 2024, all of the $225 million of Series 2010A tax-exempt bonds issued for the benefit of CECONY, bearing interest at a weekly rate, were redeemed.