XML 15 R33.htm IDEA: XBRL DOCUMENT
v3.3.0.814

Allowance for Probable Loan Losses (Details 2) - USD ($) $ in Thousands | Sep. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | $ 56,382 | $ 76,171
Loans Individually Evaluated for Impairment, Allowance | 1,756 | 12,221
Loans Collectively Evaluated for Impairment, Recorded Investment | 5,866,590 | 5,603,074
Loans Collectively Evaluated for Impairment, Allowance | 63,504 | 52,607
Commercial |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 31,265 | 40,175
Loans Individually Evaluated for Impairment, Allowance | 1,174 | 9,112
Loans Collectively Evaluated for Impairment, Recorded Investment | 981,126 | 1,049,311
Loans Collectively Evaluated for Impairment, Allowance | 19,351 | 13,240
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 | 6,349 | 10,876
Loans Individually Evaluated for Impairment, Allowance | 100 | 1,890
Loans Collectively Evaluated for Impairment, Recorded Investment | 1,648,900 | 1,404,101
Loans Collectively Evaluated for Impairment, Allowance | 14,166 | 11,065
Commercial real estate: farmland and commercial |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 9,642 | 14,166
Loans Individually Evaluated for Impairment, Allowance | 482 | 1,219
Loans Collectively Evaluated for Impairment, Recorded Investment | 1,943,066 | 1,887,233
Loans Collectively Evaluated for Impairment, Allowance | 19,143 | 17,464
Commercial real estate: multifamily |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 812 | 835
Loans Collectively Evaluated for Impairment, Recorded Investment | 107,470 | 115,864
Loans Collectively Evaluated for Impairment, Allowance | 805 | 846
Residential: first lien |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 5,294 | 5,840
Loans Collectively Evaluated for Impairment, Recorded Investment | 403,982 | 416,186
Loans Collectively Evaluated for Impairment, Allowance | 3,680 | 3,589
Residential: junior lien |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 1,028 | 2,895
Loans Collectively Evaluated for Impairment, Recorded Investment | 538,396 | 485,405
Loans Collectively Evaluated for Impairment, Allowance | 4,533 | 4,683
Consumer |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 1,243 | 1,384
Loans Collectively Evaluated for Impairment, Recorded Investment | 57,043 | 59,753
Loans Collectively Evaluated for Impairment, Allowance | 642 | 660
Foreign |  |
Loan loss allowances, impaired financing receivable, evaluated individually or collectively |  |
Loans Individually Evaluated for Impairment, Recorded Investment | 749 |
Loans Collectively Evaluated for Impairment, Recorded Investment | 186,607 | 185,221
Loans Collectively Evaluated for Impairment, Allowance | $ 1,184 | $ 1,060

X
- Definition The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1
Namespace Prefix: | us-gaap_
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
- Definition The balance of financing receivables that were collectively evaluated for impairment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524 + Details
Name: | us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The balance of financing receivables that were individually evaluated for impairment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524 + Details
Name: | us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=iboc_CommercialRealEstateOtherConstructionAndLandDevelopmentReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=iboc_ResidentialFirstMortgageFinancingReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=iboc_ResidentialSecondMortgageFinancingReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=us-gaap_ConsumerLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=iboc_ForeignReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |