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Note 1 - Summary of Significant Accounting Policies (Details Textual) | 12 Months Ended
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Dec. 31, 2025 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Number of Reportable Segments | 1 |  |
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss | $ 660,076,000 | $ 714,853,000 |
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Excluding Accrued Interest | 0 | 0 |
Goodwill | $ 13,615,000 | 13,615,000 |
Number of Reporting Units | 1 |  |
Advertising Expense | $ 1,151,000 | $ 951,000 | $ 768,000
Cumulative Effect, Period of Adoption, Adjustment [Member] |  |  |
Increase (Decrease) in Retained Earnings | (2,300,000) |  |
Metro Bancshares, Inc [Member] |  |  |
Goodwill | $ 13,600,000 |  |
Minimum [Member] |  |  |
Property, Plant and Equipment, Useful Life | 3 years |  |
Lessee, Operating Lease, Renewal Term | 1 year |  |
Minimum [Member] | Performance Shares [Member] |  |  |
Property, Plant and Equipment, Useful Life | 0.00% |  |
Maximum [Member] |  |  |
Property, Plant and Equipment, Useful Life | 39 years 6 months |  |
Lessee, Operating Lease, Renewal Term | 5 years |  |
Maximum [Member] | Performance Shares [Member] |  |  |
Property, Plant and Equipment, Useful Life | 150.00% |  |

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