Pension Benefits - Additional Information (Details) $ in Millions	6 Months Ended
Jun. 30, 2026 USD ($)
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected future employer contributions, next fiscal year	$ 58
Contributions made by employer	12
CECONY \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected future employer contributions, next fiscal year	5
CECONY \| Pension Benefits \| Subsidiaries
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected future employer contributions, next fiscal year	52
Contributions made by employer	11
CECONY \| External Trust \| Subsidiaries
Defined Benefit Plan Disclosure [Line Items]
Contributions made by employer	$ 4

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