Capitalization - Carrying Amounts and Fair Values of Long-Term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Unamortized debt expense	$ 216	$ 226
Carrying Amount
Debt Instrument [Line Items]
Long-Term Debt (including current portion)	22,673	23,044
Fair Value
Debt Instrument [Line Items]
Long-Term Debt (including current portion)	19,311	26,287
CECONY \| Subsidiaries
Debt Instrument [Line Items]
Unamortized debt discount	186	193
CECONY \| Carrying Amount \| Subsidiaries
Debt Instrument [Line Items]
Long-Term Debt (including current portion)	18,389	18,382
CECONY \| Fair Value \| Subsidiaries
Debt Instrument [Line Items]
Long-Term Debt (including current portion)	$ 15,465	$ 21,382

Amount, after accumulated amortization, of debt discount.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28541-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI https://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

Name:	us-gaap_DebtInstrumentUnamortizedDiscount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant