Annual report pursuant to Section 13 and 15(d)

Commitments and Contingencies (Details)

v2.4.1.9
Commitments and Contingencies (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Commitments and Contingencies [Line Items]    
Loans and Leases Receivable, Commitments, Fixed Rates $ 39,922us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates $ 35,189us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates
Loans and Leases Receivable, Commitments, Variable Rates 52,814us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates 43,572us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates
Loans And Leases Receivable Commitments 92,736nwin_LoansAndLeasesReceivableCommitments 78,761nwin_LoansAndLeasesReceivableCommitments
Consumer Loan [Member]    
Commitments and Contingencies [Line Items]    
Loans and Leases Receivable, Commitments, Fixed Rates 11,037us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates
/ us-gaap_FinancialInstrumentAxis
= us-gaap_ConsumerLoanMember
10,734us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates
/ us-gaap_FinancialInstrumentAxis
= us-gaap_ConsumerLoanMember
Loans and Leases Receivable, Commitments, Variable Rates 0us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates
/ us-gaap_FinancialInstrumentAxis
= us-gaap_ConsumerLoanMember
0us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates
/ us-gaap_FinancialInstrumentAxis
= us-gaap_ConsumerLoanMember
Loans And Leases Receivable Commitments 11,037nwin_LoansAndLeasesReceivableCommitments
/ us-gaap_FinancialInstrumentAxis
= us-gaap_ConsumerLoanMember
10,734nwin_LoansAndLeasesReceivableCommitments
/ us-gaap_FinancialInstrumentAxis
= us-gaap_ConsumerLoanMember
Commercial Real Estate [Member]    
Commitments and Contingencies [Line Items]    
Loans and Leases Receivable, Commitments, Fixed Rates 8,534us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates
/ us-gaap_FinancialInstrumentAxis
= us-gaap_CommercialRealEstateMember
6,718us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates
/ us-gaap_FinancialInstrumentAxis
= us-gaap_CommercialRealEstateMember
Loans and Leases Receivable, Commitments, Variable Rates 6,842us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates
/ us-gaap_FinancialInstrumentAxis
= us-gaap_CommercialRealEstateMember
0us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates
/ us-gaap_FinancialInstrumentAxis
= us-gaap_CommercialRealEstateMember
Loans And Leases Receivable Commitments 15,376nwin_LoansAndLeasesReceivableCommitments
/ us-gaap_FinancialInstrumentAxis
= us-gaap_CommercialRealEstateMember
6,718nwin_LoansAndLeasesReceivableCommitments
/ us-gaap_FinancialInstrumentAxis
= us-gaap_CommercialRealEstateMember
Commercial Participations Purchased [Member]    
Commitments and Contingencies [Line Items]    
Loans and Leases Receivable, Commitments, Fixed Rates 83us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates
/ us-gaap_FinancialInstrumentAxis
= nwin_CommercialParticipationsPurchasedMember
1,293us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates
/ us-gaap_FinancialInstrumentAxis
= nwin_CommercialParticipationsPurchasedMember
Loans and Leases Receivable, Commitments, Variable Rates 0us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates
/ us-gaap_FinancialInstrumentAxis
= nwin_CommercialParticipationsPurchasedMember
5,522us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates
/ us-gaap_FinancialInstrumentAxis
= nwin_CommercialParticipationsPurchasedMember
Loans And Leases Receivable Commitments 83nwin_LoansAndLeasesReceivableCommitments
/ us-gaap_FinancialInstrumentAxis
= nwin_CommercialParticipationsPurchasedMember
6,815nwin_LoansAndLeasesReceivableCommitments
/ us-gaap_FinancialInstrumentAxis
= nwin_CommercialParticipationsPurchasedMember
Residential Real Estate Including Home Equity [Member]    
Commitments and Contingencies [Line Items]    
Loans and Leases Receivable, Commitments, Fixed Rates 19,010us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates
/ us-gaap_FinancialInstrumentAxis
= nwin_ResidentialRealEstateIncludingHomeEquityMember
14,716us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates
/ us-gaap_FinancialInstrumentAxis
= nwin_ResidentialRealEstateIncludingHomeEquityMember
Loans and Leases Receivable, Commitments, Variable Rates 6,052us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates
/ us-gaap_FinancialInstrumentAxis
= nwin_ResidentialRealEstateIncludingHomeEquityMember
8,768us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates
/ us-gaap_FinancialInstrumentAxis
= nwin_ResidentialRealEstateIncludingHomeEquityMember
Loans And Leases Receivable Commitments 25,062nwin_LoansAndLeasesReceivableCommitments
/ us-gaap_FinancialInstrumentAxis
= nwin_ResidentialRealEstateIncludingHomeEquityMember
23,484nwin_LoansAndLeasesReceivableCommitments
/ us-gaap_FinancialInstrumentAxis
= nwin_ResidentialRealEstateIncludingHomeEquityMember
Commercial business [Member]    
Commitments and Contingencies [Line Items]    
Loans and Leases Receivable, Commitments, Fixed Rates 1,258us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates
/ us-gaap_FinancialInstrumentAxis
= nwin_CommercialBusinessMember
1,728us-gaap_LoansAndLeasesReceivableCommitmentsFixedRates
/ us-gaap_FinancialInstrumentAxis
= nwin_CommercialBusinessMember
Loans and Leases Receivable, Commitments, Variable Rates 39,920us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates
/ us-gaap_FinancialInstrumentAxis
= nwin_CommercialBusinessMember
29,282us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates
/ us-gaap_FinancialInstrumentAxis
= nwin_CommercialBusinessMember
Loans And Leases Receivable Commitments $ 41,178nwin_LoansAndLeasesReceivableCommitments
/ us-gaap_FinancialInstrumentAxis
= nwin_CommercialBusinessMember
$ 31,010nwin_LoansAndLeasesReceivableCommitments
/ us-gaap_FinancialInstrumentAxis
= nwin_CommercialBusinessMember