Note 4 - Investment Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Due in one year or less, Fair value	$ 8,814
Due after one year through five years, Fair value	159,745
Due after five years through ten years, Fair value	247,158
Due after ten years, Fair value	74,465
Total investment securities available-for-sale, Fair value	490,182	$ 546,525
Due in one year or less, Amortized cost	8,895
Due after one year through five years, Amortized cost	179,738
Due after five years through ten years, Amortized cost	296,154
Due after ten years, Amortized cost	91,391
Investment securities available-for-sale, debt securities amortized cost	$ 576,178	$ 649,217

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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