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| 0000860413-15-000018-index.html | 2015-08-05 18:01:13 | |
| 0000860413-15-000018.txt | 2015-08-05 18:01:13 | |
 0000860413-15-000018-xbrl.zip | 331210 | 2015-08-05 18:01:13 |
| fibk-20150630.xml | 4111895 | 2015-08-05 18:01:13 |
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| fibk-20150630x10q.htm | 2439816 | 2015-08-05 18:01:13 |
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| fibk-20150630xex32.htm | 4886 | 2015-08-05 18:01:13 |
| fibk-20150630_cal.xml | 144377 | 2015-08-05 18:01:13 |
| fibk-20150630_def.xml | 448473 | 2015-08-05 18:01:13 |
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| fibk-20150630_pre.xml | 542733 | 2015-08-05 18:01:13 |
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| report.css | 2767 | 2015-08-05 18:01:13 |
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