Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000860413-26-000075-index-headers.html | 2026-07-09 16:02:59 | |
| 0000860413-26-000075-index.html | 2026-07-09 16:02:59 | |
| 0000860413-26-000075.txt | 2026-07-09 16:02:59 | |
 0000860413-26-000075-xbrl.zip | 9856 | 2026-07-09 16:02:59 |
| fibk-20260709.htm | 30662 | 2026-07-09 16:02:59 |
| fibk-20260709.xsd | 1773 | 2026-07-09 16:02:59 |
| fibk-20260709_htm.xml | 2723 | 2026-07-09 16:02:59 |
| fibk-20260709_lab.xml | 21885 | 2026-07-09 16:02:59 |
| fibk-20260709_pre.xml | 12502 | 2026-07-09 16:02:59 |
| FilingSummary.xml | 1618 | 2026-07-09 16:02:59 |
| MetaLinks.json | 16849 | 2026-07-09 16:02:59 |
| R1.htm | 38077 | 2026-07-09 16:02:59 |
| report.css | 2766 | 2026-07-09 16:02:59 |
| Show.js | 1084 | 2026-07-09 16:02:59 |