XML 47 R62.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Allowance for Probable Loan Losses (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011
Allowance for probable loan losses |  |
Balance at the beginning of the period | $ 84,192 | $ 84,482
Losses charged to allowance | (58,346) | (22,899)
Recoveries credited to allowance | 4,388 | 5,291
Net losses charged to allowance | (53,958) | (17,608)
Provision (credit) charged to operations | 27,959 | 17,318
Balance at the end of the period | 58,193 | 84,192
Commercial |  |
Allowance for probable loan losses |  |
Balance at the beginning of the period | 26,617 | 22,046
Losses charged to allowance | (34,721) | (16,130)
Recoveries credited to allowance | 3,547 | 4,126
Net losses charged to allowance | (31,174) | (12,004)
Provision (credit) charged to operations | 16,189 | 16,575
Balance at the end of the period | 11,632 | 26,617
Commercial real estate: other construction and land development |  |
Allowance for probable loan losses |  |
Balance at the beginning of the period | 19,940 | 26,695
Losses charged to allowance | (7,617) | (1,467)
Recoveries credited to allowance | 229 | 171
Net losses charged to allowance | (7,388) | (1,296)
Provision (credit) charged to operations | 168 | (5,459)
Balance at the end of the period | 12,720 | 19,940
Risks related to family development loans |  |
Minimum number of family development loans | 1 |
Maximum number of family development loans | 4 |
Commercial real estate: farmland and commercial |  |
Allowance for probable loan losses |  |
Balance at the beginning of the period | 24,227 | 16,340
Losses charged to allowance | (13,724) | (1,955)
Recoveries credited to allowance | 220 | 296
Net losses charged to allowance | (13,504) | (1,659)
Provision (credit) charged to operations | 11,157 | 9,546
Balance at the end of the period | 21,880 | 24,227
Commercial real estate: multifamily |  |
Allowance for probable loan losses |  |
Balance at the beginning of the period | 1,003 | 53
Provision (credit) charged to operations | (309) | 950
Balance at the end of the period | 694 | 1,003
Residential: first lien |  |
Allowance for probable loan losses |  |
Balance at the beginning of the period | 4,562 | 10,059
Losses charged to allowance | (227) | (805)
Recoveries credited to allowance | 13 | 28
Net losses charged to allowance | (214) | (777)
Provision (credit) charged to operations | 42 | (4,720)
Balance at the end of the period | 4,390 | 4,562
Residential: junior lien |  |
Allowance for probable loan losses |  |
Balance at the beginning of the period | 4,760 | 2,611
Losses charged to allowance | (1,190) | (1,304)
Recoveries credited to allowance | 195 | 300
Net losses charged to allowance | (995) | (1,004)
Provision (credit) charged to operations | 683 | 3,153
Balance at the end of the period | 4,448 | 4,760
Consumer |  |
Allowance for probable loan losses |  |
Balance at the beginning of the period | 1,724 | 6,241
Losses charged to allowance | (756) | (1,067)
Recoveries credited to allowance | 184 | 211
Net losses charged to allowance | (572) | (856)
Provision (credit) charged to operations | 137 | (3,661)
Balance at the end of the period | 1,289 | 1,724
Foreign |  |
Allowance for probable loan losses |  |
Balance at the beginning of the period | 1,359 | 437
Losses charged to allowance | (111) | (171)
Recoveries credited to allowance |  | 159
Net losses charged to allowance | (111) | (12)
Provision (credit) charged to operations | (108) | 934
Balance at the end of the period | $ 1,140 | $ 1,359

X
- Definition Reflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, net of collections of loans and lease receivables which had previously been fully or partially charged off as bad debts. + References No definition available. + Details
Name: | iboc_AllowanceForLoanAndLeaseLossesWriteOffsNet
Namespace Prefix: | iboc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Reflects an add back to the net allowance balance for loans and lease receivables for recoveries on previously charged off loan receivables. + References No definition available. + Details
Name: | iboc_AllowanceForLoansAndLeasesLossesRecoveriesOfBadDebts
Namespace Prefix: | iboc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Reflects the maximum number of family development loans that include restrictive underwriting standards that inhibit the buys from obtaining long term financing and excessive housing and lot inventory in the market. + References No definition available. + Details
Name: | iboc_MaximumNumberOfFamilyDevelopmentLoans
Namespace Prefix: | iboc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Reflects the minimum number of family development loans that include restrictive underwriting standards that inhibit the buys from obtaining long term financing and excessive housing and lot inventory in the market. + References No definition available. + Details
Name: | iboc_MinimumNumberOfFamilyDevelopmentLoans
Namespace Prefix: | iboc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | iboc_RisksRelatedToFamilyDevelopmentLoansAbstract
Namespace Prefix: | iboc_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Reflects the gross amount charged against earnings during the period as credit losses (bad debt expense) based on review of the loan and lease portfolio and application of the methodology for estimating credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 114 -Paragraph 20 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph d -Article 9 + Details
Name: | us-gaap_AllowanceForLoanAndLeaseLossesProvisionForLossGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_AllowanceForLoanAndLeaseLossesRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Reflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, typically because they are considered to be not salvageable or have been purchased by unconsolidated collection entities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 114 -Paragraph 20 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph d -Article 9 + Details
Name: | us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 5 -Paragraph 8, 9 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Section 563c.102 -Paragraph 8 -Subparagraph a(ii) -Chapter V -Subsection I -LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy. Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph d -Article 9 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 114 -Paragraph 20 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 6 -Section L -Subsection 1 + Details
Name: | us-gaap_LoansAndLeasesReceivableAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant