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Note 8 - Commitments and Contingencies (Details Textual) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff (Recovery) | $ 3,985,000 | $ 1,597,000 | $ 6,886,000 | $ 4,315,000 |
Proceeds from Sale, Loan, Held-for-Sale |  |  | 379,654,000 | 430,421,000 |
Other Liabilities | 35,880,000 |  | 35,880,000 |  | $ 31,036,000
Holdback Reserve For Guaranteed Loans [Member] |  |  |  |  |
Other Liabilities | $ 1,800,000 |  | 1,800,000 |  | 2,000,000
Federal Home Loan Bank of Des Moines [Member] |  |  |  |  |
Proceeds from Sale, Loan, Held-for-Sale |  |  | $ 8,400,000 |  |
Escrow Holdback Relative to Outstanding Credit Enhancement (CE) Obligation, Percentage | 10.00% |  | 10.00% |  |
Escrow Holdback Relative to Outstanding Credit Enhancement (CE) Obligation | $ 39,000 |  | $ 39,000 |  |
Federal Home Loan Bank of Des Moines [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |  |  |  |
Proceeds from Sale, Loan, Held-for-Sale |  |  | 0 |  | 0
Federal Home Loan Bank of Des Moines [Member] | Recourse [Member] |  |  |  |  |
First Loss Account (FLA) | 581,000 |  | 581,000 |  |
Credit Enhancement (CE) Obligation | $ 389,000 |  | $ 389,000 |  |
Credit Enhancement (CE) Obligation, Percentage of Outstanding Loans | 4.60% |  | 4.60% |  |
Commercial Real Estate Portfolio Segment [Member] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff (Recovery) | $ 2,300,000 | (0) | $ 2,300,000 | (0) |
Unfunded Loan Commitment [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 2,100,000 |  | 2,100,000 |  | $ 1,400,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff (Recovery) | $ 457,000 | $ 78,000 | 675,000 | $ 24,000 |
Commercial and Speculative Construction and Development [Member] | Commercial Real Estate Portfolio Segment [Member] | Commitments to Extend Credit [Member] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Increase/Decrease in Provisions |  |  | $ 85,700,000 |  |

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