Capitalization - Schedule of Carrying Amounts and Fair Values of Long-Term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Debt Instrument [Line Items]
Long-term debt (including current portion)	$ 26,843	$ 25,551
Unamortized debt expense	257	249
Carrying Amount
Debt Instrument [Line Items]
Long-term debt (including current portion)	27,093	25,801
Fair Value
Debt Instrument [Line Items]
Long-term debt (including current portion)	24,595	23,633
CECONY
Debt Instrument [Line Items]
Long-term debt (including current portion)	25,351	24,060
Unamortized debt discount	249	240
CECONY \| Carrying Amount
Debt Instrument [Line Items]
Long-term debt (including current portion)	25,601	24,310
CECONY \| Fair Value
Debt Instrument [Line Items]
Long-term debt (including current portion)	$ 23,273	$ 22,291

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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+ Details

- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References + Details

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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+ Details