Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000860413-26-000092-index-headers.html | 2026-09-16 14:06:28 | |
| 0000860413-26-000092-index.html | 2026-09-16 14:06:28 | |
| 0000860413-26-000092.txt | 2026-09-16 14:06:28 | |
 0000860413-26-000092-xbrl.zip | 27714 | 2026-09-16 14:06:28 |
| fibk-20260914.htm | 35018 | 2026-09-16 14:06:28 |
| fibk-20260914.xsd | 1773 | 2026-09-16 14:06:28 |
| fibk-20260914xex101xleeemp.htm | 109773 | 2026-09-16 14:06:28 |
| fibk-20260914_htm.xml | 2723 | 2026-09-16 14:06:28 |
| fibk-20260914_lab.xml | 21885 | 2026-09-16 14:06:28 |
| fibk-20260914_pre.xml | 12502 | 2026-09-16 14:06:28 |
| FilingSummary.xml | 1618 | 2026-09-16 14:06:28 |
| MetaLinks.json | 16849 | 2026-09-16 14:06:28 |
| R1.htm | 38076 | 2026-09-16 14:06:28 |
| report.css | 2766 | 2026-09-16 14:06:28 |
| Show.js | 1084 | 2026-09-16 14:06:28 |