DeferredCompensationArrangementWithIndividualUnitsIssuedAnnuallyPerIndividualPrice

No definition available.

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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

+ References

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.

+ Details

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- Definition

Unrecognized Share Based Compensation Restricted Stock And Unit Expense Weighted Average Amortization Period Remaining Years

+ References

No definition available.

+ Details

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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

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-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

-Subparagraph (l)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (j)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

-URI http://asc.fasb.org/extlink&oid=6515339

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a),(b)

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- Definition

The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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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

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

+ References

+ Details

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Net number of share options (or share units) granted during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

+ Details

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

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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 $)	3 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards, LTIP		5,000,000
Stock options vesting period		3 years
Stock options granted		0	0
Intrinsic value for outstanding options		$ 6,000,000	$ 8,000,000
Intrinsic value for exercised options		2,000,000	5,000,000
Cash received for payment of the exercise price		5,000,000	14,000,000
Remaining contractual life, years		1 year
Income tax benefit	13,000,000	476,000,000	600,000,000	600,000,000
Number of units issued		32,114
Number of units issued annually to each individual price		$ 59.16
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		864,281	665,718	721,520
Weighted average share price per share, on shares purchased on open market		$ 57.24	$ 59.72	$ 52.50
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
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit		10,000,000		2,000,000
TSR Portion [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Adjustment percentage used for Performance awards		50.00%
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		150.00%
TSR Portion [Member] \| Officers [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		200.00%
Performance-Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period		1
Common stock received upon vesting		1
Compensation expense to be recognized		18,000,000
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period		3 years
Performance RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period		3 years
1996 Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards issued to officers and employees		0
EIP Portion [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Adjustment percentage used for Performance awards		50.00%
EIP 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%
EIP Portion [Member] \| Officers [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		200.00%
CECONY [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value for outstanding options		5,000,000	6,000,000
Income tax benefit	7,000,000	520,000,000	529,000,000	558,000,000
CECONY [Member] \| Time Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized in future periods		1,000,000
Weighted average period		1
CECONY [Member] \| Performance-Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period		1
Compensation expense to be recognized		$ 15,000,000
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting period		10 years