Capitalization - Long-term Debt, Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
CECONY \| Tax-Exempt Debt
Debt Instrument [Line Items]
Debt instrument, face amount	$ 225	$ 450

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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