XML 34 R43.htm IDEA: XBRL DOCUMENT v2.4.1.9
LOANS RECEIVABLE (Details 4) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
Impaired Loans Receivable [Line Items]    
Recorded Investment with No Specific Valuation Allowance $ 5,578us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment $ 5,589us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
Recorded Investment with Specific Valuation Allowance 1,851us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment 1,861us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
Total Recorded Investment 7,429us-gaap_ImpairedFinancingReceivableRecordedInvestment 7,450us-gaap_ImpairedFinancingReceivableRecordedInvestment
Unpaid Contractual Principal Balance 8,384us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance 8,337us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
Related Specific Valuation Allowance 70us-gaap_ImpairedFinancingReceivableRelatedAllowance 72us-gaap_ImpairedFinancingReceivableRelatedAllowance
Commercial Business Loans [Member]    
Impaired Loans Receivable [Line Items]    
Recorded Investment with No Specific Valuation Allowance 740us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialLoanMember		 759us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialLoanMember
Recorded Investment with Specific Valuation Allowance 185us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialLoanMember		 192us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialLoanMember
Total Recorded Investment 925us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialLoanMember		 951us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialLoanMember
Unpaid Contractual Principal Balance 987us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialLoanMember		 1,042us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialLoanMember
Related Specific Valuation Allowance 3us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialLoanMember		 4us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialLoanMember
Consumer Loan [Member]    
Impaired Loans Receivable [Line Items]    
Recorded Investment with No Specific Valuation Allowance 328us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_ConsumerLoanMember		 385us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_ConsumerLoanMember
Recorded Investment with Specific Valuation Allowance 132us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_ConsumerLoanMember		 133us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_ConsumerLoanMember
Total Recorded Investment 460us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_ConsumerLoanMember		 518us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_ConsumerLoanMember
Unpaid Contractual Principal Balance 490us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_ConsumerLoanMember		 521us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_ConsumerLoanMember
Related Specific Valuation Allowance 5us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_ConsumerLoanMember		 9us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_ConsumerLoanMember
Multi-family and commercial real estate [Member]    
Impaired Loans Receivable [Line Items]    
Recorded Investment with No Specific Valuation Allowance 966us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 967us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Recorded Investment with Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Total Recorded Investment 966us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 967us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Unpaid Contractual Principal Balance 1,195us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 1,197us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Related Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Multi-family and commercial real estate [Member] | Industrial Property [Member]    
Impaired Loans Receivable [Line Items]    
Recorded Investment with No Specific Valuation Allowance 21us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_IndustrialPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 22us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_IndustrialPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Recorded Investment with Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_IndustrialPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_IndustrialPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Total Recorded Investment 21us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_IndustrialPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 22us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_IndustrialPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Unpaid Contractual Principal Balance 26us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_IndustrialPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 28us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_IndustrialPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Related Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_IndustrialPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_IndustrialPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Multi-family and commercial real estate [Member] | Office Building [Member]    
Impaired Loans Receivable [Line Items]    
Recorded Investment with No Specific Valuation Allowance 546us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OfficeBuildingMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 546us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OfficeBuildingMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Recorded Investment with Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OfficeBuildingMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OfficeBuildingMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Total Recorded Investment 546us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OfficeBuildingMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 546us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OfficeBuildingMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Unpaid Contractual Principal Balance 750us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OfficeBuildingMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 750us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OfficeBuildingMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Related Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OfficeBuildingMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OfficeBuildingMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Multi-family and commercial real estate [Member] | Retail Site [Member]    
Impaired Loans Receivable [Line Items]    
Recorded Investment with No Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_RetailSiteMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_RetailSiteMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Recorded Investment with Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_RetailSiteMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_RetailSiteMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Total Recorded Investment 0us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_RetailSiteMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_RetailSiteMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Unpaid Contractual Principal Balance 0us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_RetailSiteMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_RetailSiteMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Related Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_RetailSiteMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_RetailSiteMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Multi-family and commercial real estate [Member] | Special use properties [Member]    
Impaired Loans Receivable [Line Items]    
Recorded Investment with No Specific Valuation Allowance 10us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OtherPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 10us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OtherPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Recorded Investment with Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OtherPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OtherPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Total Recorded Investment 10us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OtherPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 10us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OtherPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Unpaid Contractual Principal Balance 24us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OtherPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 24us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OtherPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Related Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OtherPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= us-gaap_OtherPropertyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Multi-family and commercial real estate [Member] | Investor owned one to four family and multi family [Member]    
Impaired Loans Receivable [Line Items]    
Recorded Investment with No Specific Valuation Allowance 389us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= nvsl_InvestorOwnedOneToFourFamilyAndMultiFamilyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 389us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= nvsl_InvestorOwnedOneToFourFamilyAndMultiFamilyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Recorded Investment with Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= nvsl_InvestorOwnedOneToFourFamilyAndMultiFamilyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= nvsl_InvestorOwnedOneToFourFamilyAndMultiFamilyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Total Recorded Investment 389us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= nvsl_InvestorOwnedOneToFourFamilyAndMultiFamilyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 389us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= nvsl_InvestorOwnedOneToFourFamilyAndMultiFamilyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Unpaid Contractual Principal Balance 395us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= nvsl_InvestorOwnedOneToFourFamilyAndMultiFamilyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 395us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= nvsl_InvestorOwnedOneToFourFamilyAndMultiFamilyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Related Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= nvsl_InvestorOwnedOneToFourFamilyAndMultiFamilyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember		 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis
= nvsl_InvestorOwnedOneToFourFamilyAndMultiFamilyMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= us-gaap_CommercialRealEstateMember
Real Estate Loans [Member] | One To Four Family [Member]    
Impaired Loans Receivable [Line Items]    
Recorded Investment with No Specific Valuation Allowance 2,901us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_OneToFourFamilyMember		 2,793us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_OneToFourFamilyMember
Recorded Investment with Specific Valuation Allowance 1,534us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_OneToFourFamilyMember		 1,536us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_OneToFourFamilyMember
Total Recorded Investment 4,435us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_OneToFourFamilyMember		 4,329us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_OneToFourFamilyMember
Unpaid Contractual Principal Balance 4,772us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_OneToFourFamilyMember		 4,555us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_OneToFourFamilyMember
Related Specific Valuation Allowance 62us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_OneToFourFamilyMember		 59us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_OneToFourFamilyMember
Real Estate Loans [Member] | Construction and Land Development [Member]    
Impaired Loans Receivable [Line Items]    
Recorded Investment with No Specific Valuation Allowance 643us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_ConstructionAndLandDevelopmentMember		 685us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_ConstructionAndLandDevelopmentMember
Recorded Investment with Specific Valuation Allowance 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_ConstructionAndLandDevelopmentMember		 0us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_ConstructionAndLandDevelopmentMember
Total Recorded Investment 643us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_ConstructionAndLandDevelopmentMember		 685us-gaap_ImpairedFinancingReceivableRecordedInvestment
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_ConstructionAndLandDevelopmentMember
Unpaid Contractual Principal Balance 940us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_ConstructionAndLandDevelopmentMember		 1,022us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_ConstructionAndLandDevelopmentMember
Related Specific Valuation Allowance $ 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_ConstructionAndLandDevelopmentMember		 $ 0us-gaap_ImpairedFinancingReceivableRelatedAllowance
/ us-gaap_FinancialInstrumentAxis
= nvsl_RealEstateLoansMember
/ us-gaap_MortgageLoansOnRealEstateLoanTypeAxis
= nvsl_ConstructionAndLandDevelopmentMember