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Equity Incentive Plan - Additional Information (Detail) (USD $)
In Thousands, except Share data, unless otherwise specified
3 Months Ended 9 Months Ended
Feb. 28, 2015
Feb. 28, 2014
Feb. 28, 2015
Feb. 28, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected period to recognize the unrecognized share based compensation cost     3 years  
Selling, general and administrative expenses        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated share based compensation $ 319us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_SellingGeneralAndAdministrativeExpensesMember
$ 312us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_SellingGeneralAndAdministrativeExpensesMember
$ 968us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_SellingGeneralAndAdministrativeExpensesMember
$ 1,036us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_SellingGeneralAndAdministrativeExpensesMember
Restricted Stock Units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Restricted stock units granted (in shares) 0us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
0us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
87,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
65,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
Unrecognized share based compensation cost 1,529us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
  1,529us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
 
Expected period to recognize the unrecognized share based compensation cost     1 year 9 months 6 days  
Vested restricted stock units 401,000elrc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedNumber
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
328,000elrc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedNumber
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
401,000elrc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedNumber
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
328,000elrc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedNumber
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
Exercise of conversion right, period     5 years  
Total excess tax benefit realized     $ 348us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
$ 156us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
2005 Equity Incentive Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Maximum number of shares authorized 1,000,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
/ us-gaap_PlanNameAxis
= elrc_TwoThousandFiveEquityIncentivePlanMember
  1,000,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
/ us-gaap_PlanNameAxis
= elrc_TwoThousandFiveEquityIncentivePlanMember