XML 58 R43.htm IDEA: XBRL DOCUMENT
v3.3.1.900

Other Borrowed Funds (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2015
Other Borrowed Funds |
Schedule of other borrowed funds |
|  | December 31, |
|  | 2015 |  | 2014 |
|  | (Dollars in Thousands) |
Federal Home Loan Bank advances—short-term |  |  |  |  |  |  |
Balance at year end |  | $ | 355,750 |  | $ | 1,067,700 |
Rate on balance outstanding at year end |  |  | 0.37 | % |  | 0.15 | %
Average daily balance |  | $ | 859,220 |  | $ | 1,077,973 |
Average rate |  |  | 0.19 | % |  | 0.16 | %
Maximum amount outstanding at any month end |  | $ | 1,239,200 |  | $ | 1,352,500 |
Federal Home Loan Bank advances—long-term(1) |  |  |  |  |  |  |
Balance at year end |  | $ | 150,000 |  | $ | 6,244 |
Rate on balance outstanding at year end |  |  | 0.31 | % |  | 3.51 | %
Average daily balance |  | $ | 5,314 |  | $ | 7,338 |
Average rate |  |  | 0.31 | % |  | 3.51 | %
Maximum amount outstanding at any month end |  | $ | 150,000 |  | $ | 8,934 |
The long‑term advances are not amortizable and consist of two advances in the amount of $75,000,000 each. The advances mature on January 13, 2017 and January 25, 2017, respectively.

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

X
- Definition Tabular disclosure of all borrowed funds not defined anywhere else in the taxonomy. Includes Federal Home Loan Bank borrowings, which are short and long-term fixed borrowings. + References No definition available. + Details
Name: | iboc_ScheduleOfOtherBorrowedFundsTableTextBlock
Namespace Prefix: | iboc_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration