Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000860413-25-000078-index-headers.html | 2025-06-02 10:03:49 | |
| 0000860413-25-000078-index.html | 2025-06-02 10:03:49 | |
| 0000860413-25-000078.txt | 2025-06-02 10:03:49 | |
 0000860413-25-000078-xbrl.zip | 21363 | 2025-06-02 10:03:49 |
| ex991fiip.htm | 39468 | 2025-06-02 10:03:49 |
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 ex991fiip002.jpg | 248473 | 2025-06-02 10:03:49 |
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 ex991fiip028.jpg | 116368 | 2025-06-02 10:03:49 |
 ex991fiip029.jpg | 88038 | 2025-06-02 10:03:49 |
| fibk-20250602.htm | 29700 | 2025-06-02 10:03:49 |
| fibk-20250602.xsd | 1773 | 2025-06-02 10:03:49 |
| fibk-20250602_htm.xml | 2723 | 2025-06-02 10:03:49 |
| fibk-20250602_lab.xml | 21885 | 2025-06-02 10:03:49 |
| fibk-20250602_pre.xml | 12502 | 2025-06-02 10:03:49 |
| FilingSummary.xml | 1618 | 2025-06-02 10:03:49 |
| MetaLinks.json | 16849 | 2025-06-02 10:03:49 |
| R1.htm | 38078 | 2025-06-02 10:03:49 |
| report.css | 2767 | 2025-06-02 10:03:49 |
| Show.js | 1085 | 2025-06-02 10:03:49 |