Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000860413-26-000034-index-headers.html | 2026-04-29 16:12:13 | |
| 0000860413-26-000034-index.html | 2026-04-29 16:12:13 | |
| 0000860413-26-000034.txt | 2026-04-29 16:12:13 | |
 0000860413-26-000034-xbrl.zip | 58320 | 2026-04-29 16:12:13 |
| fibk-20260331x8kpr.htm | 772846 | 2026-04-29 16:12:13 |
| fibk-20260429.htm | 32445 | 2026-04-29 16:12:13 |
| fibk-20260429.xsd | 2366 | 2026-04-29 16:12:13 |
| fibk-20260429_def.xml | 10969 | 2026-04-29 16:12:13 |
| fibk-20260429_htm.xml | 2723 | 2026-04-29 16:12:13 |
| fibk-20260429_lab.xml | 25241 | 2026-04-29 16:12:13 |
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 fibslogo2linea04a.jpg | 165531 | 2026-04-29 16:12:13 |
| FilingSummary.xml | 2091 | 2026-04-29 16:12:13 |
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 mar2026ip001.jpg | 138744 | 2026-04-29 16:12:13 |
 mar2026ip002.jpg | 283965 | 2026-04-29 16:12:13 |
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 mar2026ip020.jpg | 111843 | 2026-04-29 16:12:13 |
| MetaLinks.json | 20416 | 2026-04-29 16:12:13 |
| R1.htm | 13588 | 2026-04-29 16:12:13 |
| R2.htm | 27029 | 2026-04-29 16:12:13 |
| report.css | 2767 | 2026-04-29 16:12:13 |
| Show.js | 1085 | 2026-04-29 16:12:13 |