Quarterly report pursuant to Section 13 or 15(d)

Loans Receivable (Details Textual)

v2.4.1.9
Loans Receivable (Details Textual) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
Financing Receivable, Modifications [Line Items]    
Financing Receivable, Individually Evaluated for Impairment $ 5,912us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment $ 6,768us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
Residential Real Estate [Member]    
Financing Receivable, Modifications [Line Items]    
Financing Receivable, Individually Evaluated for Impairment 929us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_ResidentialRealEstateMember 		 
Impaired Loans [Member]    
Financing Receivable, Modifications [Line Items]    
Impaired Financing Receivable, Unpaid Principal Balance, Total 1,900us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_InvestmentTypeAxis
= nwin_ImpairedLoansMember 		 
Residential Real Estate Including Home Equity [Member]    
Financing Receivable, Modifications [Line Items]    
Impaired Financing Receivable, Unpaid Principal Balance, Total 2,269us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_FinancialInstrumentAxis
= nwin_ResidentialRealEstateIncludingHomeEquityMember 		1,258us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
/ us-gaap_FinancialInstrumentAxis
= nwin_ResidentialRealEstateIncludingHomeEquityMember
Financing Receivable, Individually Evaluated for Impairment $ 336us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
/ us-gaap_FinancialInstrumentAxis
= nwin_ResidentialRealEstateIncludingHomeEquityMember 		$ 97us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
/ us-gaap_FinancialInstrumentAxis
= nwin_ResidentialRealEstateIncludingHomeEquityMember