Represents the amount of total fair value of additional cash-based awards on the grant date.

No definition available.

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Represents the expense recognized during the period arising from cash-based compensation arrangements with employees, directors and certain consultants qualifying for treatment as employees.

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No definition available.

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Represents the percentage of awards vesting in each of the succeeding two years.

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No definition available.

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Represents the percentage of awards vesting in the first year.

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No definition available.

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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

Represents the non-elective employer contributions as a percentage of eligible compensation under a defined contribution plan.

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No definition available.

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Represents the percentage of vested awards forfeitable in the event of certain termination events.

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No definition available.

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Represents the equity-based awards granted during the period as a percentage of units purchased.

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No definition available.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest to be recognized in next fiscal year.

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No definition available.

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As of the balance sheet date, unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest to be recognized on an accelerated basis for each tranche of the award over the requisite service period.

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No definition available.

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As of the balance sheet date, unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest to be recognized upon a specified capital transaction when the right to such amounts becomes nonforfeitable.

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No definition available.

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- Definition

Represents the issuance cost of awards issued under the share-based compensation plan.

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No definition available.

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Represents the amount of total fair value of equity-based awards on the grant date.

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No definition available.

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Represents the expense related to share-based compensation arrangements that will occur until those events that give rise to a payout on shares become probable of occurring.

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No definition available.

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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.

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The amount of the cost recognized during the period for defined contribution plans.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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No definition available.

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Unrecognized cost of unvested share-based compensation awards.

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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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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Long-Term Incentive Compensation / Retirement 401(k) Plan (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended		0 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended		0 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Sep. 18, 2013 EPE Holdings II	Dec. 31, 2013 EPE Holdings II	Dec. 31, 2012 Class A Matching Grants	Dec. 31, 2013 Class A Matching Grants	Dec. 31, 2013 Class A Matching Grants Class A units Parent	May 24, 2012 MIPs	Dec. 31, 2012 MIPs	Dec. 31, 2013 MIPs
Cash-Based Long Term Incentive
Awards vesting in the first year (as a percent)		50.00%
Awards vesting in each of the succeeding two years (as a percent)		25.00%
Compensation cost recorded	$ 8	$ 16
Long-Term Incentive Compensation / Retirement 401(k) Plan
Fair value on the grant date							24				74
Fair value of cash-based awards on the grant date		22	24
Unrecognized compensation cost		12					7				40
Unrecognized compensation cost to be recognized in 2014		9					3
Vesting period		3 years									5 years
Percentage of vested awards forfeitable in the event of certain termination events											25.00%
Risk free rate (as a percent)									0.77%
Expiration term									5 years
Volatility rate (as a percent)									73.00%
Compensation expense recorded				0		11	6			15	19
Unrecognized compensation cost to be recognized on an accelerated basis for each tranche of the award											21
Unrecognized compensation cost to be recognized upon a specified capital transaction											19
Grants as a percentage of the Class A units purchased								50.00%
Recognition period of fair value as compensation cost							4 years
Requisite service period											5 years
Retirement 401(k) Plan
Maximum matching contributions as a percentage of eligible compensation		6.00%
Non-elective employer contributions as a percentage of eligible compensation		5.00%
Matching and non-elective employer contributions by employer	7	12
Compensation expense that will occur until those events that give rise to a payout become probable of occurring					0
Award issuance cost											$ 0