Annual report pursuant to Section 13 and 15(d)

Shareholders' Equity Market Based Stock Option Awards (Details)

v2.4.1.9
Shareholders' Equity Market Based Stock Option Awards (Details) (USD $)
3 Months Ended 12 Months Ended 0 Months Ended
Feb. 01, 2014
Jan. 31, 2015
Feb. 01, 2014
Feb. 02, 2013
Oct. 03, 2012
Nov. 18, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Share-based compensation   $ 3,860,000us-gaap_ShareBasedCompensation $ 3,217,000us-gaap_ShareBasedCompensation $ 3,257,000us-gaap_ShareBasedCompensation    
Allocated Share-based Compensation Expense   2,537,000us-gaap_AllocatedShareBasedCompensationExpense 2,405,000us-gaap_AllocatedShareBasedCompensationExpense 1,682,000us-gaap_AllocatedShareBasedCompensationExpense    
Risk Free Interest Rate   1.00%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate        
Granted, weighted average grant date fair value $ 3.96us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue $ 3.92us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue   $ 1.03us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue    
Expected Term   6 years 6 years 6 years    
2011 Omnibus Incentive Plan [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Granted   232,000evlv_ShareBasedCompensationArrangementOptionsGrantsInPeriodGross
/ us-gaap_PlanNameAxis
= evlv_A2011OmnibusIncentivePlanMember
       
Options outstanding 3,083,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
/ us-gaap_PlanNameAxis
= evlv_A2011OmnibusIncentivePlanMember
2,463,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
/ us-gaap_PlanNameAxis
= evlv_A2011OmnibusIncentivePlanMember
3,083,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
/ us-gaap_PlanNameAxis
= evlv_A2011OmnibusIncentivePlanMember
     
Granted, weighted average grant date fair value   $ 4.65us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_PlanNameAxis
= evlv_A2011OmnibusIncentivePlanMember
       
Number of consecutive trading days         20 days  
Market Based Stock Options Awards [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Granted         2,125,000evlv_ShareBasedCompensationArrangementOptionsGrantsInPeriodGross
/ us-gaap_PlanNameAxis
= evlv_MarketBasedStockOptionsAwardsMember
 
Stock Option Plans, Exercise Price Range, Lower Range Limit         6.00us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit
/ us-gaap_PlanNameAxis
= evlv_MarketBasedStockOptionsAwardsMember
 
Risk Free Interest Rate         0.38%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
/ us-gaap_PlanNameAxis
= evlv_MarketBasedStockOptionsAwardsMember
 
Weighted average volatility rate         78.00%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageVolatilityRate
/ us-gaap_PlanNameAxis
= evlv_MarketBasedStockOptionsAwardsMember
 
Options outstanding   1,715,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
/ us-gaap_PlanNameAxis
= evlv_MarketBasedStockOptionsAwardsMember
       
Granted, weighted average grant date fair value         4.00us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_PlanNameAxis
= evlv_MarketBasedStockOptionsAwardsMember
 
Number of tranches         3evlv_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNumberOfTranches
/ us-gaap_PlanNameAxis
= evlv_MarketBasedStockOptionsAwardsMember
 
Expected Term         3 years 3 months 18 days  
Grant date fair value         1,998,000evlv_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantDateFairValue
/ us-gaap_PlanNameAxis
= evlv_MarketBasedStockOptionsAwardsMember
 
Tranche 1 [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Award vesting rights         .5  
Granted, weighted average grant date fair value         0.93us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_PlanNameAxis
= evlv_Tranche1Member
 
Expected Term         15 months  
Tranche 2 [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Award vesting rights         .25  
Stock Option Plans, Exercise Price Range, Lower Range Limit         8.00us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit
/ us-gaap_PlanNameAxis
= evlv_Tranche2Member
 
Granted, weighted average grant date fair value         0.95us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_PlanNameAxis
= evlv_Tranche2Member
 
Expected Term         20 months  
Tranche 3 [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Award vesting rights         .25  
Stock Option Plans, Exercise Price Range, Lower Range Limit         10.00us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerRangeLimit
/ us-gaap_PlanNameAxis
= evlv_Tranche3Member
 
Granted, weighted average grant date fair value         0.95us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_PlanNameAxis
= evlv_Tranche3Member
 
Expected Term         24 months  
Restricted Stock [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Share-based compensation $ 812,000us-gaap_ShareBasedCompensation
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
$ 1,323,000us-gaap_ShareBasedCompensation
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
  $ 1,575,000us-gaap_ShareBasedCompensation
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
   
Risk Free Interest Rate         0.32%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
1.03%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
Granted, weighted average grant date fair value           $ 4.91us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
Expected Term         2 years 9 months 18 days  
Restricted Stock [Member] | Tranche 1 [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Granted, weighted average grant date fair value         1.48us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
/ us-gaap_PlanNameAxis
= evlv_Tranche1Member
 
Expected Term         15 months  
Restricted Stock [Member] | Tranche 2 [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Granted, weighted average grant date fair value         1.39us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
/ us-gaap_PlanNameAxis
= evlv_Tranche2Member
 
Expected Term         20 months  
Restricted Stock [Member] | Tranche 3 [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Granted, weighted average grant date fair value         1.31us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
/ us-gaap_PlanNameAxis
= evlv_Tranche3Member
 
Expected Term         24 months