LTIP weighted average price.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, contribution amount by employee for matching

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Maximum employee contribution per year

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Maximum employer contribution

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares, LTIP Plan

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Performance RSU's, adjustment percentage

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Performance RSU's, Factor used, high range

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Performance RSU's, Factor used, low range

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Stock Options Expiration Period

+ References

No definition available.

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- Definition

Unrecognized Share Based Compensation Restricted Stock and Unit Expense Weighted Average Amortization Period, Remaining Term

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

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-Subparagraph (SAB TOPIC 14.F)

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-Paragraph 2

-Subparagraph (h)(1)(i)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

Number of shares issued pursuant to the terms of a deferred compensation arrangement.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-Paragraph 2

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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- Definition

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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- Definition

The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

+ References

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Stock-Based Compensation - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards, LTIP	5,000,000
Stock options vesting period	3 years
Income tax benefit	$ 12,000,000	$ 11,000,000	$ 8,000,000
Number of units issued	37,972
LTIP Weighted Average Price	$ 55.51ed_LtipWeightedAveragePrice
Maximum employer contribution match	1
Amount employee contribution for employer match	9
Maximum employee investment per year	25,000
Maximum percentage allowed to invest	20.00%
Shares purchased on the open market	708,276	864,281	665,718
Weighted average share price per share, on shares purchased on open market	$ 56.23	$ 57.24	$ 59.72
Time Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized in future periods	2,000,000
Weighted average period	1 year
CECONY [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit	10,000,000	10,000,000	7,000,000
CECONY [Member] \| Time Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized in future periods	2,000,000
Weighted average period	1 year
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit	1,000,000	10,000,000
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period	3 years
TSR Portion [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Adjustment percentage used for Performance awards	50.00%
Factor used for adjustment of Performance awards, low end	0.00%
Factor used for adjustment of Performance awards, high end	200.00%
Non-TSR Portion [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Adjustment percentage used for Performance awards	50.00%
Factor used for adjustment of Performance awards, low end	0.00%
Factor used for adjustment of Performance awards, high end	200.00%
Non-TSR Portion [Member] \| Management Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Factor used for adjustment of Performance awards, low end	0.00%
Factor used for adjustment of Performance awards, high end	120.00%
Performance-Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock received upon vesting	One share
Compensation expense to be recognized	25,000,000
Weighted average period	1 year
Performance-Based Restricted Stock [Member] \| CECONY [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense to be recognized	$ 19,000,000
Weighted average period	1 year
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting period	10 years