Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000860413-25-000057-index-headers.html | 2025-04-29 16:09:18 | |
| 0000860413-25-000057-index.html | 2025-04-29 16:09:18 | |
| 0000860413-25-000057.txt | 2025-04-29 16:09:18 | |
 0000860413-25-000057-xbrl.zip | 53892 | 2025-04-29 16:09:18 |
| fibk-20250331x8kpr.htm | 781402 | 2025-04-29 16:09:18 |
| fibk-20250429.htm | 32902 | 2025-04-29 16:09:18 |
| fibk-20250429.xsd | 1773 | 2025-04-29 16:09:18 |
| fibk-20250429_htm.xml | 2723 | 2025-04-29 16:09:18 |
| fibk-20250429_lab.xml | 21885 | 2025-04-29 16:09:18 |
| fibk-20250429_pre.xml | 12502 | 2025-04-29 16:09:18 |
 fibslogo2linea04.jpg | 165531 | 2025-04-29 16:09:18 |
| FilingSummary.xml | 1618 | 2025-04-29 16:09:18 |
| Financial_Report.xlsx | 5713 | 2025-04-29 16:09:18 |
| mar2025ip.htm | 33333 | 2025-04-29 16:09:18 |
 mar2025ip001.jpg | 138678 | 2025-04-29 16:09:18 |
 mar2025ip002.jpg | 268606 | 2025-04-29 16:09:18 |
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 mar2025ip016.jpg | 277592 | 2025-04-29 16:09:18 |
 mar2025ip017.jpg | 112761 | 2025-04-29 16:09:18 |
 mar2025ip018.jpg | 105765 | 2025-04-29 16:09:18 |
| MetaLinks.json | 16850 | 2025-04-29 16:09:18 |
| R1.htm | 38078 | 2025-04-29 16:09:18 |
| report.css | 2767 | 2025-04-29 16:09:18 |
| Show.js | 1085 | 2025-04-29 16:09:18 |