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Note 1 - Summary of Significant Accounting Policies (Details Textual) | 12 Months Ended
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Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | $ 982,664,000 | $ 1,034,121,000 | [1] |
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Ending Balance |  |  |  | $ 0
Goodwill, Ending Balance | $ 13,615,000 | 13,615,000 |  |
Number of Reporting Units | 1 |  |  |
Advertising Expense | $ 768,000 | $ 447,000 |  | $ 499,000
Metro Bancshares, Inc [Member] |  |  |  |
Goodwill, Ending Balance | $ 13,600,000 |  |  |
Minimum [Member] |  |  |  |
Property, Plant and Equipment, Useful Life (Year) | 3 years |  |  |
Lessee, Operating Lease, Renewal Term (Year) | 1 year |  |  |
Minimum [Member] | Performance Shares [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Shares Vested Upon Certain Performance Metrics, Percentage | 0.00% |  |  |
Maximum [Member] |  |  |  |
Property, Plant and Equipment, Useful Life (Year) | 39 years 6 months |  |  |
Lessee, Operating Lease, Renewal Term (Year) | 5 years |  |  |
Maximum [Member] | Performance Shares [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Shares Vested Upon Certain Performance Metrics, Percentage | 150.00% |  |  |
[1] | derived from audited financial statements.

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