Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000860413-26-000041-index-headers.html | 2026-05-13 17:12:56 | |
| 0000860413-26-000041-index.html | 2026-05-13 17:12:56 | |
| 0000860413-26-000041.txt | 2026-05-13 17:12:56 | |
 0000860413-26-000041-xbrl.zip | 23553 | 2026-05-13 17:12:56 |
| fibk-20260511.htm | 33858 | 2026-05-13 17:12:56 |
| fibk-20260511.xsd | 1773 | 2026-05-13 17:12:56 |
| fibk-20260511xex101xtransi.htm | 81573 | 2026-05-13 17:12:56 |
| fibk-20260511_htm.xml | 2723 | 2026-05-13 17:12:56 |
| fibk-20260511_lab.xml | 21885 | 2026-05-13 17:12:56 |
| fibk-20260511_pre.xml | 12502 | 2026-05-13 17:12:56 |
| FilingSummary.xml | 1618 | 2026-05-13 17:12:56 |
| MetaLinks.json | 16849 | 2026-05-13 17:12:56 |
| R1.htm | 38074 | 2026-05-13 17:12:56 |
| report.css | 2766 | 2026-05-13 17:12:56 |
| Show.js | 1084 | 2026-05-13 17:12:56 |