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SHARE-BASED COMPENSATION - RSU Activity - Summary of Change (Details) (USD $)
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3 Months Ended |
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Mar. 31, 2015
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| Number of Restricted Stock Units [Roll Forward] | |
| RSUs beginning | 1,258,685us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber |
| RSUs awarded | 645,601us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod |
| RSUs released | (336,229)us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod |
| RSUs forfeited | (13,499)us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod |
| RSUs ending | 1,554,558us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber |
| Weighted Average Purchase Price RSUs | $ 0etm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAveragePurchasePrice |
| Weighted Average Remaining Contractual Term (Years) RSUs | 1 year 8 months 12 days |
| Aggregate Intrinsic Value RSUs | $ 18,887,880etm_AggregateInstrinsicValueOfRestrictedStockUnits |
| Number of RSUs vested and expected to vest | 1,414,787etm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestNumber |
| Weighted Average Purchase Price of RSUs vested and expected to vest | $ 0etm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestWeightedAveragePurchasePrice |
| Weighted Average Remaining Contractual Term (Years) of RUSs vested and expected to vest | 1 year 7 months 6 days |
| Aggregate Intrinsic Value RSUs vested and expected to vest | 16,161,731etm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestAggregateIntrinsicValue |
| Number of RSUs exercisable | 84,603etm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisable |
| Weighted Average Purchase Price of RUSs exercisable | $ 0etm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAveragePurchasePriceExcercisable |
| Weighted Average Remaining Contractual Term (Years) of RUSs exercisable | 0 years |
| Aggregate Intrinsic Value RSUs exercisable | 1,027,926etm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExcercisableAggregateInstrinsicValue |
| Weighted average remaining recognition period in years | 2 years 4 months 24 days |
| Unamortized compensation expense, net of estimated forfeitures | $ 10,435,775etm_UnamortizedCompensationExpenseForRestrictedStockUnits |
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- Definition
Share based compensation for restricted stock units aggregate instinsic value. No definition available.
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- Definition
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Excercisable Aggregate Instrinsic Value. No definition available.
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- Definition
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercisable No definition available.
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- Definition
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercisable Weighted Average Contractual Term. No definition available.
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- Definition
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested And Expected To Vest Aggregate Intrinsic Value No definition available.
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- Definition
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested And Expected To Vest Contractual Term No definition available.
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- Definition
As of the balance sheet date, the number of Retricted Stock Units into which fully vested and expected to vest stock options outstanding can be converted under the plan. No definition available.
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- Definition
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested And Expected To Vest Weighted Average Purchase Price. No definition available.
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- Definition
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Weighted Average Purchase Price. No definition available.
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- Definition
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Weighted Average Purchase Price Excercisable. No definition available.
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- Definition
Unamortized compensation expense for restricted stock units net of estimated forfeitures. No definition available.
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- Definition
Period over which the unamortized compensation expense will be recognized for restricted stock units. No definition available.
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- Definition
The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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