Risk Assessment and Remediation Plan, Period

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- Definition

Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Percentage of public utility's requested equity to capital, including debt and equity.

+ References

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- Definition

Amount of public utility's requested rate increase (decrease) with regulatory agency.

+ References

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- Definition

Percentage of public utility's requested return on equity.

+ References

No definition available.

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- Definition

The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Regulatory Matters - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended			12 Months Ended
	Feb. 16, 2017	Jan. 31, 2017	Oct. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Public Utilities, General Disclosures [Line Items]
Regulatory liabilities				$ 1,905.0	$ 1,977.0
FERC \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Requested return on equity (percent)		10.70%
Requested equity capital structure (percent)		48.00%
Rockland Electric Company (RECO) \| NJBPU \| Subsequent Event \| Rockland Electric Company (RECO) \| Electric
Public Utilities, General Disclosures [Line Items]
Interim rate increase, amount	$ 1.7
Requested return on equity (percent)	9.60%
Requested equity capital structure (percent)	49.70%
Rockland Electric Company (RECO) \| FERC
Public Utilities, General Disclosures [Line Items]
Requested rate increase, amount				11.8
Rockland Electric Company (RECO) \| FERC \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Requested rate increase, amount		$ 19.7
CECONY
Public Utilities, General Disclosures [Line Items]
Regulatory liabilities				1,712.0	$ 1,789.0
CECONY \| June 2014 Plastic Fusion Proceeding
Public Utilities, General Disclosures [Line Items]
Regulatory liabilities				$ 27.0
CECONY \| Subsequent Event \| June 2014 Plastic Fusion Proceeding
Public Utilities, General Disclosures [Line Items]
Loss from settlement	$ 126.0
CECONY \| NYSPSC
Public Utilities, General Disclosures [Line Items]
Risk assessment and remediation plan, period			3 years