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

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

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

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- Definition

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

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- Definition

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

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

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

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- Definition

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

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Shares

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- Definition

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

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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
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- Definition

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

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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.

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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.

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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.

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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.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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

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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.

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- Definition

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

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Stock-Based Compensation - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards, LTIP (up to)	5,000,000
Stock options vesting period (years)	3 years
Income tax benefit	$ 14,000,000	$ 12,000,000	$ 11,000,000
Number of units issued	30,724
LTIP Weighted Average Price (dollars per share)	$ 61.31
Maximum employer contribution match (up to)	$ 1
Amount employee contribution for employer match	9
Maximum employee investment per year (up to)	$ 25,000
Maximum percentage allowed to invest (not more than)	20.00%
Shares purchased on the open market	761,784	708,276	864,281
Weighted average share price per share, on shares purchased on open market	$ 62.75	$ 56.23	$ 57.24
Time Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized in future periods	$ 2,000,000
Nonvested awards, compensation cost not yet recognized, period for recognition (years)	1 year
CECONY
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit	$ 12,000,000	$ 10,000,000	$ 10,000,000
CECONY \| Time Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense recognized in future periods	$ 2,000,000
Nonvested awards, compensation cost not yet recognized, period for recognition (years)	1 year
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit	$ 1,000,000	$ 1,000,000	$ 10,000,000
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period (years)	3 years
TSR Portion
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 (percent)	0.00%
Factor used for adjustment of Performance awards, high end (percent)	200.00%
Non-TSR Portion
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 (percent)	0.00%
Factor used for adjustment of Performance awards, high end (percent)	200.00%
Non-TSR Portion \| Management Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Factor used for adjustment of Performance awards, low end (percent)	0.00%
Factor used for adjustment of Performance awards, high end (percent)	120.00%
Performance-Based Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock received upon vesting	one share
Common stock received upon vesting (shares)	1
Compensation expense to be recognized	$ 29,000,000
Weighted average period (years)	1 year
Performance-Based Restricted Stock \| CECONY
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense to be recognized	$ 23,000,000
Weighted average period (years)	1 year
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option expiration period (years)	10 years