Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000860413-25-000036-index-headers.html | 2025-03-19 17:15:30 | |
| 0000860413-25-000036-index.html | 2025-03-19 17:15:30 | |
| 0000860413-25-000036.txt | 2025-03-19 17:15:30 | |
 0000860413-25-000036-xbrl.zip | 9865 | 2025-03-19 17:15:30 |
| fibk-20250314.htm | 30605 | 2025-03-19 17:15:30 |
| fibk-20250314.xsd | 1773 | 2025-03-19 17:15:30 |
| fibk-20250314_htm.xml | 2723 | 2025-03-19 17:15:30 |
| fibk-20250314_lab.xml | 21885 | 2025-03-19 17:15:30 |
| fibk-20250314_pre.xml | 12502 | 2025-03-19 17:15:30 |
| FilingSummary.xml | 1618 | 2025-03-19 17:15:30 |
| Financial_Report.xlsx | 5713 | 2025-03-19 17:15:30 |
| MetaLinks.json | 16850 | 2025-03-19 17:15:30 |
| R1.htm | 38077 | 2025-03-19 17:15:30 |
| report.css | 2766 | 2025-03-19 17:15:30 |
| Show.js | 1084 | 2025-03-19 17:15:30 |