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|---|---|---|
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| 0000860413-17-000017-index.html | 2017-05-08 18:09:41 | |
| 0000860413-17-000017.txt | 2017-05-08 18:09:41 | |
 0000860413-17-000017-xbrl.zip | 356991 | 2017-05-08 18:09:41 |
| fibk-20160930.xml | 4132740 | 2017-05-08 18:09:41 |
| fibk-20160930.xsd | 59325 | 2017-05-08 18:09:41 |
| fibk-20160930_cal.xml | 153828 | 2017-05-08 18:09:41 |
| fibk-20160930_def.xml | 477519 | 2017-05-08 18:09:41 |
| fibk-20160930_lab.xml | 926201 | 2017-05-08 18:09:41 |
| fibk-20160930_pre.xml | 576199 | 2017-05-08 18:09:41 |
| fibk-20170331x10q.htm | 2218217 | 2017-05-08 18:09:41 |
| fibk-20170331xex311.htm | 12204 | 2017-05-08 18:09:41 |
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| fibk-20170331xex32.htm | 4703 | 2017-05-08 18:09:41 |
| FilingSummary.xml | 34738 | 2017-05-08 18:09:41 |
| Financial_Report.xlsx | 104561 | 2017-05-08 18:09:41 |
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| report.css | 2767 | 2017-05-08 18:09:41 |
| Show.js | 1410 | 2017-05-08 18:09:41 |