Current Expected Credit Losses - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase (decrease) in allowance for uncollectible accounts resulting from COVID-19 pandemic	$ 34	$ (78)
Subsidiaries \| CECONY
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase (decrease) in allowance for uncollectible accounts resulting from COVID-19 pandemic	$ 30	$ (78)

Amount of increase (decrease) in allowance for credit loss on accounts receivable.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration