XML 40 R23.htm IDEA: XBRL DOCUMENT v2.4.1.9
1. NATURE OF OPERATIONS, BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)
 3 Months Ended
Mar. 31, 2015
Accounts Receivable [Member] | Customer A  
Concentration percentage 53.00%us-gaap_ConcentrationRiskPercentage1
/ us-gaap_ConcentrationRiskByBenchmarkAxis
= us-gaap_AccountsReceivableMember
/ us-gaap_MajorCustomersAxis
= evsi_CustomerAMember
Accounts Receivable [Member] | Customer B  
Concentration percentage 29.00%us-gaap_ConcentrationRiskPercentage1
/ us-gaap_ConcentrationRiskByBenchmarkAxis
= us-gaap_AccountsReceivableMember
/ us-gaap_MajorCustomersAxis
= evsi_CustomerBMember
Accounts Receivable [Member] | Customer C  
Concentration percentage 17.00%us-gaap_ConcentrationRiskPercentage1
/ us-gaap_ConcentrationRiskByBenchmarkAxis
= us-gaap_AccountsReceivableMember
/ us-gaap_MajorCustomersAxis
= evsi_CustomerCMember
Revenues [Member] | Customer A  
Concentration percentage 83.00%us-gaap_ConcentrationRiskPercentage1
/ us-gaap_ConcentrationRiskByBenchmarkAxis
= us-gaap_SalesMember
/ us-gaap_MajorCustomersAxis
= evsi_CustomerAMember
Revenues [Member] | Customer B  
Concentration percentage 13.00%us-gaap_ConcentrationRiskPercentage1
/ us-gaap_ConcentrationRiskByBenchmarkAxis
= us-gaap_SalesMember
/ us-gaap_MajorCustomersAxis
= evsi_CustomerBMember