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Note 14 - Goodwill and Other Intangible Assets (Details Textual) |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jan. 22, 2016 | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($)
Goodwill |  | $ 3,592,000 |  | $ 3,592,000 |  | $ 3,592,000
Goodwill, Impairment Loss |  |  |  |  |  | 0
Amortization of Intangible Assets |  | $ 787,000 | $ 897,000 | 2,426,000 | $ 2,757,000 |
Core Deposits [Member] |  |  |  |  |  |
Impairment of Intangible Assets, Finite-Lived |  |  |  | 0 |  |
Amortization of Intangible Assets |  |  |  | $ 2,426,000 |  | $ 3,633,000
Bank of America [Member] |  |  |  |  |  |
Number of Businesses Acquired | 4 |  |  |  |  |
Columbia State Bank [Member] | Core Deposits [Member] |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life (Year) |  | 10 years |  | 10 years |  |
Anchor Bank [Member] | Core Deposits [Member] |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life (Year) |  | 10 years |  | 10 years |  |

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