Defined Benefit Plan, Target Allocation Percentage, total

No definition available.

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- Details

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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=21915506&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=21915506&loc=d3e2446-114920

+ Details

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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=21915506&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=21915506&loc=d3e1928-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ 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, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Debt Securities [Member]	Dec. 31, 2011 Debt Securities [Member]	Dec. 31, 2010 Debt Securities [Member]	Dec. 31, 2012 Equity Securities [Member]	Dec. 31, 2011 Equity Securities [Member]	Dec. 31, 2010 Equity Securities [Member]	Dec. 31, 2013 Scenario, Forecast [Member]	Dec. 31, 2013 Scenario, Forecast [Member] Equity Security [Member]	Dec. 31, 2013 Scenario, Forecast [Member] Debt Securities [Member]
Schedule Of Other Postretirement Benefits [Line Items]
Plan Assets	100.00%	100.00%	100.00%	38.00%	38.00%	33.00%	62.00%	62.00%	67.00%
Target Allocation, Minimum											57.00%	26.00%
Target Allocation, Maximum											73.00%	44.00%
Target Allocation Range, Total										100.00%