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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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

Current Expected Credit Losses - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase in allowance for uncollectible accounts resulting from COVID-19 pandemic	$ (78)		$ 19
Subsidiaries \| CECONY
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase in allowance for uncollectible accounts resulting from COVID-19 pandemic		$ 20