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| 0000860413-14-000008-index.html | 2014-05-02 13:11:24 | |
| 0000860413-14-000008.txt | 2014-05-02 13:11:24 | |
 0000860413-14-000008-xbrl.zip | 290614 | 2014-05-02 13:11:24 |
| fibk-20140331.xml | 3306752 | 2014-05-02 13:11:24 |
| fibk-20140331.xsd | 55614 | 2014-05-02 13:11:24 |
| fibk-20140331x10q.htm | 1964320 | 2014-05-02 13:11:24 |
| fibk-20140331xex311.htm | 12088 | 2014-05-02 13:11:24 |
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| fibk-20140331xex32.htm | 4923 | 2014-05-02 13:11:24 |
| fibk-20140331_cal.xml | 138115 | 2014-05-02 13:11:24 |
| fibk-20140331_def.xml | 396106 | 2014-05-02 13:11:24 |
| fibk-20140331_lab.xml | 823828 | 2014-05-02 13:11:24 |
| fibk-20140331_pre.xml | 483000 | 2014-05-02 13:11:24 |
| FilingSummary.xml | 27593 | 2014-05-02 13:11:24 |
| Financial_Report.xls | 2626138 | 2014-05-02 13:11:24 |
| Financial_Report.xlsx | 294470 | 2014-05-02 13:11:24 |
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| report.css | 2740 | 2014-05-02 13:11:24 |
| Show.js | 1410 | 2014-05-02 13:11:24 |