Pension Benefits - Schedule of Employer Contribution to Defined Savings Plan (Details) - Defined Contribution Savings Plan - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Employer contribution to the defined savings plan	$ 57	$ 57	$ 55
CECONY
Defined Benefit Plan Disclosure [Line Items]
Employer contribution to the defined savings plan	$ 51	$ 48	$ 46

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.

No definition available.

Name:	us-gaap_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration