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Public Utilities, Removal Costs

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Public Utilities, Service And Repair Costs

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Tax Cuts And Jobs Act Of 2017, Change In Tax Rate, Regulatory Liabilities, Income Tax Benefit

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Tax Cuts And Jobs Act Of 2017, Change In Tax Rate, Regulatory Liabilities, Income Tax Benefit, Subject To Normalization Requirements

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Tax Cuts And Jobs Act Of 2017, Income Tax Expense (Benefit)

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Amount of regulatory costs not yet approved by the regulatory authority.

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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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Amount of public utility's interim rate increase (decrease) allowed while waiting final decision of regulatory agency.

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Discloses the amount of construction work in process that is included in the rate making process at period end.

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The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

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A noncash adjustment to the provision established for storm damage by an oil, gas, or utility company.

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Amount of operating expense for routine plant maintenance, repairs and operations of regulated operation.

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Regulatory Matters - Other Regulatory Matters (Details) customer in Thousands, $ in Millions		1 Months Ended	3 Months Ended		6 Months Ended
	Apr. 01, 2018 USD ($)	Mar. 31, 2018 USD ($)	Jun. 30, 2018 USD ($) customer	Mar. 31, 2018 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Public Utilities, General Disclosures [Line Items]
Regulatory assets			$ 4,187.0		$ 4,187.0		$ 4,333.0
CECONY
Public Utilities, General Disclosures [Line Items]
Regulatory assets			$ 3,779.0		3,779.0		$ 3,925.0
Impact in regulatory liability resulting from TCJA					217.0
CECONY \| Future Income Tax
Public Utilities, General Disclosures [Line Items]
Impact in regulatory liability resulting from TCJA					3,513.0
CECONY \| Accelerated Tax Depreciation Benefits
Public Utilities, General Disclosures [Line Items]
Impact in regulatory liability resulting from TCJA					2,542.0
CECONY \| Deferred Income Tax Charge, Amortized Over Remaining Life of Asset
Public Utilities, General Disclosures [Line Items]
Impact in regulatory liability resulting from TCJA					971.0
CECONY \| Electric \| Hurricane
Public Utilities, General Disclosures [Line Items]
Number of customers affected with interrupted service \| customer			209
Restoration costs			$ 126.0
Operation and maintenance expenses			17.0
Operation and maintenance expenses charged against a storm reserve			75.0
Capital expenditures			28.0		28.0
Removal costs			$ 6.0
O&R \| Future Income Tax
Public Utilities, General Disclosures [Line Items]
Impact in regulatory liability resulting from TCJA					161.0
O&R \| Accelerated Tax Depreciation Benefits
Public Utilities, General Disclosures [Line Items]
Impact in regulatory liability resulting from TCJA					126.0
O&R \| Deferred Income Tax Charge, Amortized Over Remaining Life of Asset
Public Utilities, General Disclosures [Line Items]
Impact in regulatory liability resulting from TCJA					35.0
O&R \| Electric \| Hurricane
Public Utilities, General Disclosures [Line Items]
Number of customers affected with interrupted service \| customer			93
Restoration costs			$ 48.0
RECO \| Electric \| Hurricane
Public Utilities, General Disclosures [Line Items]
Number of customers affected with interrupted service \| customer			44
Restoration costs			$ 18.0
NYSPSC \| CECONY \| MTA Subway Power Outage
Public Utilities, General Disclosures [Line Items]
Regulatory costs			180.0		180.0
Regulatory assets			150.0		150.0
NYSPSC \| CECONY \| MTA Subway Power Outage \| Scenario, Forecast
Public Utilities, General Disclosures [Line Items]
Regulatory costs						$ 84.0
Regulatory assets						82.0
NYSPSC \| CECONY \| MTA Subway Power Outage \| Electric
Public Utilities, General Disclosures [Line Items]
Regulatory costs			$ 30.0		$ 30.0
NYSPSC \| CECONY \| MTA Subway Power Outage \| Electric \| Scenario, Forecast
Public Utilities, General Disclosures [Line Items]
Regulatory costs						$ 2.0
NJBPU \| RECO \| Electric
Public Utilities, General Disclosures [Line Items]
Approved interim rate decrease	$ 2.9
Net benefit of the TCJA				$ 1.0
FERC \| RECO
Public Utilities, General Disclosures [Line Items]
Impact in regulatory liability resulting from TCJA		$ 28.0
Impact in regulatory liability resulting from TCJA, subject to normalization requirements		$ 16.0