XML 43 R33.htm IDEA: XBRL DOCUMENT
v3.22.2

Allowance for Credit Losses (Impairment By Loan Class) (Details) - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | $ 1,341 | $ 1,667
Loans Individually Evaluated for Impairment, Allowance | 70 | 99
Loans Collectively Evaluated for Impairment, Recorded Investment | 7,025,788 | 7,207,484
Loans Collectively Evaluated for Impairment, Allowance | 112,502 | 110,275
Commercial, financial and agricultural | Domestic | Commercial. |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 238 | 298
Loans Individually Evaluated for Impairment, Allowance |  | 29
Loans Collectively Evaluated for Impairment, Recorded Investment | 1,475,126 | 1,501,554
Loans Collectively Evaluated for Impairment, Allowance | 25,577 | 23,149
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 333 | 562
Loans Collectively Evaluated for Impairment, Recorded Investment | 2,542,421 | 2,710,494
Loans Collectively Evaluated for Impairment, Allowance | 35,270 | 35,654
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 123 | 131
Loans Collectively Evaluated for Impairment, Recorded Investment | 233,822 | 284,405
Loans Collectively Evaluated for Impairment, Allowance | 2,856 | 3,291
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 564 | 589
Loans Individually Evaluated for Impairment, Allowance | 70 | 70
Loans Collectively Evaluated for Impairment, Recorded Investment | 1,732,670 | 1,667,524
Loans Collectively Evaluated for Impairment, Allowance | 36,643 | 35,320
Real estate - mortgage | Domestic | Residential: first lien |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 83 | 87
Loans Collectively Evaluated for Impairment, Recorded Investment | 405,303 | 403,571
Loans Collectively Evaluated for Impairment, Allowance | 4,137 | 4,073
Real estate - mortgage | Domestic | Residential Junior Lien |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Collectively Evaluated for Impairment, Recorded Investment | 437,356 | 464,173
Loans Collectively Evaluated for Impairment, Allowance | 6,894 | 7,754
Consumer | Domestic |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Collectively Evaluated for Impairment, Recorded Investment | 40,815 | 40,966
Loans Collectively Evaluated for Impairment, Allowance | 270 | 272
Foreign. | Foreign |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Collectively Evaluated for Impairment, Recorded Investment | 158,275 | 134,797
Loans Collectively Evaluated for Impairment, Allowance | $ 855 | $ 762

X
- Definition The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment. + References No definition available. + Details
Name: | iboc_FinancingReceivableCollectivelyEvaluatedForImpairmentAllowanceForCreditLosses
Namespace Prefix: | iboc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The balance of financing receivables that were collectively evaluated for impairment. + References No definition available. + Details
Name: | iboc_FinancingReceivableEvaluatedForImpairmentCollectively
Namespace Prefix: | iboc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The balance of financing receivables that were individually evaluated for impairment. + References No definition available. + Details
Name: | iboc_FinancingReceivableEvaluatedForImpairmentIndividually
Namespace Prefix: | iboc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment. + References No definition available. + Details
Name: | iboc_FinancingReceivableIndividuallyEvaluatedForImpairmentAllowanceForCreditLosses
Namespace Prefix: | iboc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=iboc_CommercialFinancialAndAgriculturalRealEstatePortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GeographicDistributionAxis=us-gaap_GeographicDistributionDomesticMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=iboc_CommercialRealEstateFarmlandAndCommercialReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=iboc_CommercialRealEstateMultifamilyReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConstructionLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LienCategoryAxis=us-gaap_SeniorLienMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LienCategoryAxis=us-gaap_JuniorLienMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=iboc_ForeignPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GeographicDistributionAxis=us-gaap_GeographicDistributionForeignMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |