Pension Benefits - Additional Information (Details) - Pension Benefits $ in Millions	3 Months Ended
	Mar. 31, 2026 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected future employer contributions, next fiscal year	$ 31
Contributions made by employer	7
CECONY
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected future employer contributions, next fiscal year	4
CECONY | Subsidiaries
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected future employer contributions, next fiscal year	25
Contributions made by employer	$ 6