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| 0000860413-26-000017-index.html | 2026-03-30 18:18:48 | |
| 0000860413-26-000017.txt | 2026-03-30 18:18:48 | |
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| fibk-20260330.htm | 3495086 | 2026-03-30 18:18:48 |
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| fibk-20260330_htm.xml | 35737 | 2026-03-30 18:18:48 |
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| MetaLinks.json | 200700 | 2026-03-30 18:18:48 |
| R1.htm | 10841 | 2026-03-30 18:18:48 |
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| R3.htm | 6546 | 2026-03-30 18:18:48 |
| R4.htm | 4370 | 2026-03-30 18:18:48 |
| report.css | 2767 | 2026-03-30 18:18:48 |
| Show.js | 1085 | 2026-03-30 18:18:48 |