Achievable Restricted Stock Units Maximum

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- Definition

Deferred Compensation Arrangement with Individual, units issued annually per individual

+ References

No definition available.

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- Definition

DeferredCompensationArrangementWithIndividualUnitsIssuedAnnuallyPerIndividualPrice

+ References

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

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

+ 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

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-Subparagraph (h)(1)(i)

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph A240

-Subparagraph g(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.

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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-Number 123R

-Paragraph 64

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-Topic 718

-SubTopic 10

-Section S99

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-Subparagraph (SAB TOPIC 14.F)

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- Definition

The number of shares issued pursuant to the terms of the deferred compensation plan as of the balance sheet date.

+ References

+ Details

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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

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- Definition

The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

+ References

Reference 1: 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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-Name Statement of Financial Accounting Standard (FAS)

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-Subparagraph a, b

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

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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 Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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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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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to 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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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 65

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

+ References

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and 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

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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

+ Details

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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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-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.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

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-Subparagraph (a)

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-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64, 65

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Stock-Based Compensation - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012 Y	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards	10,000,000
Stock option awards, LTIP	10,000,000
Restricted stock	4,000,000
Stock option vesting period	3 years
Intrinsic value for outstanding options	$ 8,000,000	$ 18,000,000
Intrinsic value for exercised options	5,000,000	21,000,000
Cash received for payment of the exercise price	14,000,000	88,000,000
Remaining contractual life, years	2 years
INCOME TAX EXPENSE	600,000,000	600,000,000	548,000,000
Total expense recognized in future periods	2,000,000
Weighted average period	1
Number of units issued annually to each individual	1,785
Number of units issued	30,242
Number of units issued annually to each individual price	$ 58.89
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	665,718	721,520	738,951
Weighted average share price per share, on shares purchased on open market	$ 59.72	$ 52.50	$ 45.52
EIP 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%
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	150.00%
Performance-based restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period	1
Unvested compensation expense	23,000,000
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
INCOME TAX EXPENSE		2,000,000	6,000,000
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting period	10 years
CECONY [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value for outstanding options	6,000,000	14,000,000
INCOME TAX EXPENSE	529,000,000	558,000,000	495,000,000
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
Unvested compensation expense	$ 19,000,000