XML 49 R15.htm IDEA: XBRL DOCUMENT
v3.3.0.814

Other Borrowed Funds | 9 Months Ended
--- | ---
Sep. 30, 2015
Other Borrowed Funds |
Other Borrowed Funds | Note 7 — Other Borrowed Funds Other borrowed funds include Federal Home Loan Bank borrowings, which are short-term and long-term borrowings issued by the FHLB of Dallas at the market price offered at the time of funding. These borrowings are secured by residential mortgage-backed investment securities and a portion of the Company’s loan portfolio. At September 30, 2015, other borrowed funds totaled $803,550,000 a decrease of 25.2% from $1,073,944,000 at December 31, 2014. The decrease in borrowings can be primarily attributed to the use of funds generated from principal paydowns on available for sale securities.

X
- References No definition available. + Details
Name: | iboc_OtherBorrowedFundsDisclosureAbstract
Namespace Prefix: | iboc_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The entire disclosure for borrowing from the Federal Home Loan Bank, including: (i) general description; (ii) title and nature of obligation; (iii) interest rate; (iv) payment terms; (v) maturity dates by year; (vi) collateral requirements; (vii) restrictive covenants; (viii) priority; (ix) conversion or redemption features; (x) carrying value of assets pledged as collateral; (xi) combined aggregate maturities for next five years; (xii) unused or available balances. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
Name: | us-gaap_FederalHomeLoanBankAdvancesDisclosureTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration