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| 0000860413-14-000013-index.html | 2014-07-31 20:18:46 | |
| 0000860413-14-000013.txt | 2014-07-31 20:18:46 | |
 0000860413-14-000013-xbrl.zip | 314973 | 2014-07-31 20:18:46 |
| fibk-20140630.xml | 3868733 | 2014-07-31 20:18:46 |
| fibk-20140630.xsd | 52887 | 2014-07-31 20:18:46 |
| fibk-20140630x10q.htm | 2375698 | 2014-07-31 20:18:46 |
| fibk-20140630xex311.htm | 12051 | 2014-07-31 20:18:46 |
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| fibk-20140630xex32.htm | 4885 | 2014-07-31 20:18:46 |
| fibk-20140630_cal.xml | 140262 | 2014-07-31 20:18:46 |
| fibk-20140630_def.xml | 407499 | 2014-07-31 20:18:46 |
| fibk-20140630_lab.xml | 835216 | 2014-07-31 20:18:46 |
| fibk-20140630_pre.xml | 496293 | 2014-07-31 20:18:46 |
| FilingSummary.xml | 28391 | 2014-07-31 20:18:46 |
| Financial_Report.xls | 3088435 | 2014-07-31 20:18:46 |
| Financial_Report.xlsx | 330019 | 2014-07-31 20:18:46 |
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| report.css | 2740 | 2014-07-31 20:18:46 |
| Show.js | 1410 | 2014-07-31 20:18:46 |