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Gain (Loss) On Commodity Contracts

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Generating Capacity Per Day

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Maximum Amount Of Funding

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Outstanding Loan

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Related Party Transaction, Lending Period

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Sales Of Natural Gas Propane Ngls And Condensate And Affiliates

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Term Of Contract

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Amount of net assets (liabilities).

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Amount of transactions with related party during the financial reporting period.

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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.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Related Party Transactions - Additional Information (Details) MMBTU in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) MMBTU	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Related Party Transaction [Line Items]
Net assets	$ 18,847,000,000	$ 18,022,000,000
CECONY
Related Party Transaction [Line Items]
Net assets	14,849,000,000	14,147,000,000	$ 12,910,000,000	$ 12,439,000,000
Sale of natural gas	59,000,000	71,000,000	83,000,000
Funding limit of CECONY to O&R (not to exceed)	$ 250,000,000
CECONY \| Related Party, Lending of Funds
Related Party Transaction [Line Items]
Lending period (not more than) (months)	12 months
CECONY \| Equity Method Investee \| Mountain Valley Pipeline
Related Party Transaction [Line Items]
Amount of transaction	$ 0	0
Contract term (years)	20 years
Generating capacity per day (in dekatherms) \| MMBTU	250
CECONY \| Equity Method Investee \| Stagecoach \| Purchased Power Costs
Related Party Transaction [Line Items]
Amount of transaction	$ 34,000,000	33,000,000	$ 28,000,000
CECONY \| Affiliated Entity \| Financial Electric Capacity Contract \| Con Edison Energy
Related Party Transaction [Line Items]
Gain (loss) on financial electric capacity contracts	(1,000,000)	(1,000,000)
O&R
Related Party Transaction [Line Items]
Net assets	807,000,000
Outstanding loans	$ 0	$ 0
CET Electric \| NY Transco
Related Party Transaction [Line Items]
Ownership interest, percentage	45.70%
CET Gas \| Mountain Valley Pipeline
Related Party Transaction [Line Items]
Percentage of equity interest owned	11.30%
Expected reduction in equity interest	8.80%