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v2.4.1.9

Allowance for Probable Loan Losses (Details 4) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Dec. 31, 2014 | Dec. 31, 2013
Interest Recognized |  |
Loans accounted for as troubled debt restructuring | $ 15,653 us-gaap_FinancingReceivableModificationsRecordedInvestment | $ 20,358 us-gaap_FinancingReceivableModificationsRecordedInvestment
Period of charge off for past due unsecured commercial loans | 90 days |
Total troubled debt restructuring | 15,653 us-gaap_FinancingReceivableModificationsRecordedInvestment | 20,358 us-gaap_FinancingReceivableModificationsRecordedInvestment
Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance | 31,765 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 31,255 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance | 44,406 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 44,638 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded | 32,232 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 34,699 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance recorded | 46,262 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 45,986 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Related Allowance | 12,221 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 16,002 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Average recorded investment: |  |
Total impaired loans with an allowance recorded | 33,286 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 31,244 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance recorded | 43,202 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 51,616 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Interest Recognized |  |
Total impaired loans with an allowance recorded | 92 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 130 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance recorded | 444 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 374 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Commercial |  |
Interest Recognized |  |
Loans accounted for as troubled debt restructuring | 2,500 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember | 150 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember
Total troubled debt restructuring | 2,500 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember | 150 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember
Commercial | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance | 19,944 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 17,178 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance | 20,231 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 17,005 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded | 20,026 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 17,177 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance recorded | 20,260 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 17,023 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Related Allowance | 9,112 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 12,234 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Average recorded investment: |  |
Total impaired loans with an allowance recorded | 19,313 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 18,019 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance recorded | 18,563 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 16,778 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Interest Recognized |  |
Total impaired loans with an allowance recorded |  | 38 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance recorded | 4 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 2 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Commercial real estate: other construction and land development |  |
Interest Recognized |  |
Loans accounted for as troubled debt restructuring | 2,254 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember | 8,860 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember
Total troubled debt restructuring | 2,254 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember | 8,860 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember
Commercial real estate: other construction and land development | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance | 6,714 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 6,818 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance | 4,162 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 7,158 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded | 6,949 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 6,825 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance recorded | 4,270 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 7,187 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Related Allowance | 1,890 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 852 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Average recorded investment: |  |
Total impaired loans with an allowance recorded | 7,183 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 6,058 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance recorded | 4,882 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 18,164 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Interest Recognized |  |
Total impaired loans with no related allowance recorded | 74 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 74 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Commercial real estate: farmland and commercial |  |
Interest Recognized |  |
Loans accounted for as troubled debt restructuring | 2,861 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember | 2,863 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember
Total troubled debt restructuring | 2,861 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember | 2,863 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember
Commercial real estate: farmland and commercial | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance | 5,107 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 7,259 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance | 9,059 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 8,779 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded | 5,257 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 10,697 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance recorded | 10,562 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 9,949 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Related Allowance | 1,219 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 2,916 us-gaap_ImpairedFinancingReceivableRelatedAllowance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Average recorded investment: |  |
Total impaired loans with an allowance recorded | 6,790 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 7,167 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Total impaired loans with no related allowance recorded | 8,664 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 7,313 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Interest Recognized |  |
Total impaired loans with an allowance recorded | 92 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 92 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Commercial real estate: multifamily | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with no related allowance | 835 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 295 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Unpaid principal balance: |  |
Total impaired loans with no related allowance recorded | 835 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 295 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Average recorded investment: |  |
Total impaired loans with no related allowance recorded | 363 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 322 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Residential: first lien |  |
Interest Recognized |  |
Loans accounted for as troubled debt restructuring | 5,313 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember | 4,887 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember
Total troubled debt restructuring | 5,313 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember | 4,887 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember
Residential: first lien | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with no related allowance | 5,840 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 6,153 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Unpaid principal balance: |  |
Total impaired loans with no related allowance recorded | 6,034 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 6,258 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Average recorded investment: |  |
Total impaired loans with no related allowance recorded | 6,293 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 4,860 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Interest Recognized |  |
Total impaired loans with no related allowance recorded | 273 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 179 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Residential: junior lien |  |
Interest Recognized |  |
Loans accounted for as troubled debt restructuring | 1,371 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember | 1,631 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember
Total troubled debt restructuring | 1,371 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember | 1,631 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember
Residential: junior lien | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with no related allowance | 2,895 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 3,206 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Unpaid principal balance: |  |
Total impaired loans with no related allowance recorded | 2,915 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 3,226 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Average recorded investment: |  |
Total impaired loans with no related allowance recorded | 3,035 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 2,347 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Interest Recognized |  |
Total impaired loans with no related allowance recorded | 90 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 99 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Consumer Loan |  |
Interest Recognized |  |
Loans accounted for as troubled debt restructuring | 1,354 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember | 1,531 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember
Total troubled debt restructuring | 1,354 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember | 1,531 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember
Consumer Loan | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with no related allowance | 1,384 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 1,606 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Unpaid principal balance: |  |
Total impaired loans with no related allowance recorded | 1,386 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 1,612 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Average recorded investment: |  |
Total impaired loans with no related allowance recorded | 1,402 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 1,380 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Interest Recognized |  |
Total impaired loans with no related allowance recorded | 3 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 1 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Foreign |  |
Interest Recognized |  |
Loans accounted for as troubled debt restructuring |  | 436 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ForeignReceivablesMember
Total troubled debt restructuring |  | 436 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ForeignReceivablesMember
Foreign | Class of financing receivable |  |
Recorded investment: |  |
Total impaired loans with no related allowance |  | 436 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ForeignReceivablesMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Unpaid principal balance: |  |
Total impaired loans with no related allowance recorded |  | 436 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ForeignReceivablesMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Average recorded investment: |  |
Total impaired loans with no related allowance recorded |  | 452 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ForeignReceivablesMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Interest Recognized |  |
Total impaired loans with no related allowance recorded |  | $ 19 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ForeignReceivablesMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember

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