Pension Benefits - Additional Information (Details) - Pension Benefits $ in Millions	9 Months Ended
Sep. 30, 2025 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Estimated future employer contributions	$ 65
Contributions made by employer	14
CECONY \| Subsidiaries
Defined Benefit Plan Disclosure [Line Items]
Estimated future employer contributions	61
Contributions made by employer	$ 12

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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+ Details

- Definition

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