XML 19 R46.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Loans - Impaired Loans - Recorded Investment, Unpaid Principal Balance and Related Allowance (Details) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2015 | Dec. 31, 2014
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Recorded Investment |  |
With no related allowance recorded | $ 25,016 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment | $ 35,011 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
With an allowance recorded | 6,910 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment | 875 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
Total impaired loans | 31,926 us-gaap_ImpairedFinancingReceivableRecordedInvestment | 35,886 us-gaap_ImpairedFinancingReceivableRecordedInvestment
Unpaid Principal Balance |  |
With no related allowance recorded | 30,106 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance | 41,003 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance
With an allowance recorded | 8,193 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance | 997 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance
Total impaired loans | 38,299 us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance | 42,000 us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
Related Allowance |  |
With an allowance recorded | 1,784 us-gaap_ImpairedFinancingReceivableRelatedAllowance | 278 us-gaap_ImpairedFinancingReceivableRelatedAllowance
Commercial |  |
Recorded Investment |  |
With no related allowance recorded | 1,897 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 1,500 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember
Unpaid Principal Balance |  |
With no related allowance recorded | 2,571 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 2,114 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember
Real estate - commercial | Owner occupied general purpose |  |
Recorded Investment |  |
With no related allowance recorded | 2,593 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 7,125 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
With an allowance recorded | 4,011 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember |
Unpaid Principal Balance |  |
With no related allowance recorded | 3,279 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 7,870 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
With an allowance recorded | 4,657 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember |
Related Allowance |  |
With an allowance recorded | 1,304 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember |
Real estate - commercial | Owner occupied special purpose |  |
Recorded Investment |  |
With no related allowance recorded | 1,154 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedSpecialPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 1,798 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedSpecialPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
With an allowance recorded | 609 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedSpecialPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember |
Unpaid Principal Balance |  |
With no related allowance recorded | 1,240 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedSpecialPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 1,941 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedSpecialPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
With an allowance recorded | 687 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedSpecialPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember |
Related Allowance |  |
With an allowance recorded | 113 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateOwnerOccupiedSpecialPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember |
Real estate - commercial | Non-owner occupied general purpose |  |
Recorded Investment |  |
With no related allowance recorded | 750 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateNonOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 4,831 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateNonOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
With an allowance recorded |  | 76 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateNonOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Unpaid Principal Balance |  |
With no related allowance recorded | 1,160 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateNonOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 5,653 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateNonOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
With an allowance recorded |  | 76 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateNonOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Related Allowance |  |
With an allowance recorded |  | 21 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateNonOwnerOccupiedGeneralPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Real estate - commercial | Non-owner occupied special purpose |  |
Recorded Investment |  |
With no related allowance recorded |  | 1,423 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateNonOwnerOccupiedSpecialPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
With an allowance recorded | 1,380 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateNonOwnerOccupiedSpecialPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember |
Unpaid Principal Balance |  |
With no related allowance recorded |  | 1,930 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateNonOwnerOccupiedSpecialPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
With an allowance recorded | 1,806 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateNonOwnerOccupiedSpecialPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember |
Related Allowance |  |
With an allowance recorded | 163 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateNonOwnerOccupiedSpecialPurposeLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember |
Real estate - commercial | Farm |  |
Recorded Investment |  |
With no related allowance recorded | 1,370 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateFarmLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember |
Unpaid Principal Balance |  |
With no related allowance recorded | 1,370 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_CommercialRealEstateFarmLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember |
Real estate - construction | Homebuilder |  |
Recorded Investment |  |
With no related allowance recorded | 1,320 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateHomebuilderLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 1,791 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateHomebuilderLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember
Unpaid Principal Balance |  |
With no related allowance recorded | 1,320 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateHomebuilderLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 1,791 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateHomebuilderLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember
Real estate - construction | All other |  |
Recorded Investment |  |
With no related allowance recorded | 240 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateOtherReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 291 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateOtherReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember
With an allowance recorded | 261 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateOtherReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 270 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateOtherReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember
Unpaid Principal Balance |  |
With no related allowance recorded | 324 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateOtherReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 323 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateOtherReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember
With an allowance recorded | 300 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateOtherReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 306 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateOtherReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember
Related Allowance |  |
With an allowance recorded | 60 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateOtherReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 98 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ConstructionRealEstateOtherReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember
Real estate - residential | Investor |  |
Recorded Investment |  |
With no related allowance recorded | 1,760 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialInvestorLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 2,595 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialInvestorLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
With an allowance recorded | 131 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialInvestorLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 135 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialInvestorLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Unpaid Principal Balance |  |
With no related allowance recorded | 2,101 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialInvestorLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 3,024 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialInvestorLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
With an allowance recorded | 144 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialInvestorLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 145 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialInvestorLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Related Allowance |  |
With an allowance recorded | 21 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialInvestorLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 24 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialInvestorLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Real estate - residential | Owner occupied |  |
Recorded Investment |  |
With no related allowance recorded | 11,602 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialOwnerOccupiedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 11,419 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialOwnerOccupiedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
With an allowance recorded | 152 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialOwnerOccupiedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 23 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialOwnerOccupiedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Unpaid Principal Balance |  |
With no related allowance recorded | 13,113 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialOwnerOccupiedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 12,816 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialOwnerOccupiedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
With an allowance recorded | 194 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialOwnerOccupiedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 65 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialOwnerOccupiedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Related Allowance |  |
With an allowance recorded | 30 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialOwnerOccupiedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 38 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialOwnerOccupiedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Real estate - residential | Revolving and junior liens |  |
Recorded Investment |  |
With no related allowance recorded | 2,330 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialRevolvingAndJuniorLiensLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 2,238 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialRevolvingAndJuniorLiensLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
With an allowance recorded | 366 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialRevolvingAndJuniorLiensLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 371 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialRevolvingAndJuniorLiensLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Unpaid Principal Balance |  |
With no related allowance recorded | 3,628 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialRevolvingAndJuniorLiensLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 3,541 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialRevolvingAndJuniorLiensLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
With an allowance recorded | 405 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialRevolvingAndJuniorLiensLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 405 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialRevolvingAndJuniorLiensLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Related Allowance |  |
With an allowance recorded | $ 93 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialRevolvingAndJuniorLiensLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | $ 97 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = osbc_ResidentialRevolvingAndJuniorLiensLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember

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