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v2.4.1.9

Allowance for Probable Loan Losses (Details 6) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2014 | Dec. 31, 2013
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Loan portfolio by credit quality indicator |  |
Portfolio, total | $ 5,679,245 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome | $ 5,199,235 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome
Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 5,328,410 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember | 4,942,387 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember
Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 54,561 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_InternalCreditAssessmentAxis = us-gaap_SpecialMentionMember | 73,077 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_InternalCreditAssessmentAxis = us-gaap_SpecialMentionMember
Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 37,674 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_InternalCreditAssessmentAxis = iboc_SpecialPassMember | 35,619 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_InternalCreditAssessmentAxis = iboc_SpecialPassMember
Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 182,429 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember | 72,259 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember
Watch List - Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 76,171 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember | 75,893 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember
Commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,089,486 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember | 1,042,642 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember
Commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 961,490 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember | 955,522 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember
Commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 38,382 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SpecialMentionMember | 2,270 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SpecialMentionMember
Commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 3,793 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_InternalCreditAssessmentAxis = iboc_SpecialPassMember | 4,389 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_InternalCreditAssessmentAxis = iboc_SpecialPassMember
Commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 45,646 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember | 46,278 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember
Commercial | Watch List - Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 40,175 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember | 34,183 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_CommercialLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember
Commercial real estate: other construction and land development |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,414,977 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember | 1,208,508 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember
Commercial real estate: other construction and land development | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,353,971 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember | 1,167,295 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember
Commercial real estate: other construction and land development | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,005 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SpecialMentionMember | 14,247 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SpecialMentionMember
Commercial real estate: other construction and land development | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 10,428 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_InternalCreditAssessmentAxis = iboc_SpecialPassMember | 9,318 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_InternalCreditAssessmentAxis = iboc_SpecialPassMember
Commercial real estate: other construction and land development | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 38,697 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember | 3,672 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember
Commercial real estate: other construction and land development | Watch List - Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 10,876 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember | 13,976 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember
Commercial real estate: farmland and commercial |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,901,399 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember | 1,750,039 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember
Commercial real estate: farmland and commercial | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,754,741 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember | 1,635,179 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember
Commercial real estate: farmland and commercial | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 11,674 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SpecialMentionMember | 56,438 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SpecialMentionMember
Commercial real estate: farmland and commercial | Watch List - Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 23,453 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_InternalCreditAssessmentAxis = iboc_SpecialPassMember | 21,912 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_InternalCreditAssessmentAxis = iboc_SpecialPassMember
Commercial real estate: farmland and commercial | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 97,365 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember | 20,472 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember
Commercial real estate: farmland and commercial | Watch List - Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 14,166 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember | 16,038 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember
Commercial real estate: multifamily |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 116,699 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember | 102,098 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember
Commercial real estate: multifamily | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 115,729 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember | 100,948 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember
Commercial real estate: multifamily | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 135 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember | 855 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember
Commercial real estate: multifamily | Watch List - Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 835 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember | 295 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_CommercialRealEstateMultifamilyReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember
Residential: first lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 422,026 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember | 438,462 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember
Residential: first lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 412,668 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember | 432,067 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember
Residential: first lien | Special Review |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 3,500 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SpecialMentionMember | 122 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SpecialMentionMember
Residential: first lien | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 18 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember | 120 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember
Residential: first lien | Watch List - Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 5,840 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember | 6,153 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialFirstMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember
Residential: junior lien |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 488,300 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember | 409,230 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember
Residential: junior lien | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 484,968 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember | 405,731 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember
Residential: junior lien | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 437 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember | 293 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember
Residential: junior lien | Watch List - Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 2,895 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember | 3,206 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ResidentialSecondMortgageFinancingReceivableMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember
Consumer Loan |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 61,137 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember | 66,414 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember
Consumer Loan | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 59,622 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember | 64,808 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember
Consumer Loan | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 131 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember |
Consumer Loan | Watch List - Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 1,384 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember | 1,606 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = us-gaap_ConsumerLoanMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember
Foreign |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 185,221 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ForeignReceivablesMember | 181,842 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ForeignReceivablesMember
Foreign | Pass |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total | 185,221 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ForeignReceivablesMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember | 180,837 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ForeignReceivablesMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_PassMember
Foreign | Watch List - Substandard |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | 569 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ForeignReceivablesMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember
Foreign | Watch List - Impaired |  |
Loan portfolio by credit quality indicator |  |
Portfolio, total |  | $ 436 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = iboc_ForeignReceivablesMember / us-gaap_InternalCreditAssessmentAxis = us-gaap_NonperformingFinancingReceivableMember

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- Definition Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5074-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522 + Details
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