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Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($) |  | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Jan. 01, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Dec. 31, 2023 | Jun. 30, 2023 | Dec. 01, 2022
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss |  | $ 0 |  | $ 0 |  |  |
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss |  | 1,500,000 |  | 1,500,000 | $ 1,600,000 |  |
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease) |  | $ 731,000 | $ 395,000 | $ 833,000 |  |  |
Commercial Portfolio Segment [Member] | Minimum [Member] |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process |  |  | $ 250,000 |  |  | $ 150,000 |
Accounting Standards Update 2016-13 [Member] | Commercial Portfolio Segment [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease) | $ 622,000 |  |  |  |  |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |  |  |  |
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss | $ 5,400,000 |  |  |  |  |  |
LBSI Insurance, LLC [Member] |  |  |  |  |  |  |
Business Acquisition, Percentage of Voting Interests Acquired |  |  |  |  |  |  | 100.00%

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