Defined Benefit Plan Target Allocation Percentage 1

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- Definition

Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(i)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(i)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2446-114920

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- Definition

Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

+ Details

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

+ Details

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Other Postretirement Benefits - Schedule of Plan Assets Allocations (Detail) (CECONY [Member], Other Postretirement Benefits [Member])	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Plan Assets	100.00%	100.00%	100.00%
Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan Assets	59.00%	61.00%	62.00%
Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan Assets	41.00%	39.00%	38.00%
Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Range, Total	100.00%
Scenario, Forecast [Member] \| Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation, Minimum	57.00%
Target Allocation, Maximum	73.00%
Scenario, Forecast [Member] \| Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation, Minimum	26.00%
Target Allocation, Maximum	44.00%