Note 6 - Investment Securities (Details Textual)	3 Months Ended
Mar. 31, 2024 USD ($) Security	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Investment Securities [Line Items]
Proceeds from sale of investment securities	$ 0	$ 9,081,000
Available-for-sale securities pledged as collateral	$ 251,927,000		$ 289,935,000
Debt Securities, Available-for-Sale, Restriction Type [Extensible Enumeration]	us-gaap:AssetPledgedAsCollateralMember		us-gaap:AssetPledgedAsCollateralMember
Other than temporary impairment, credit losses recognized in earnings	$ 0	0
Available-for-sale, amortized cost	565,864,000		$ 576,178,000
Available-for-sale	481,596,000		490,182,000
Investment equity securities	6,217,000		$ 5,910,000
Proceeds from sale of investment equity securities	$ 1,210,000	709,000
Pooled Trust Preferred Security [Member]
Investment Securities [Line Items]
Number of trust preferred securities \| Security	1
Available-for-sale, amortized cost	$ 59,000
Available-for-sale	52,000
Equity Securities [Member]
Investment Securities [Line Items]
Income tax expense (benefit) related to net recognized gains (losses) on sales of securities	96,000	(44,000)
Debt Securities [Member]
Investment Securities [Line Items]
Income tax expense (benefit) related to net realized gains (losses) on sales of securities	$ 0	$ 54,000

Income tax expense (benefit) during the period related to net realized gains (losses) on sales of securities.

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Income tax expense (benefit) during the period related to net recognized gains (losses) on sales of securities.

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Investment securities.

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The number of trust preferred securities held by the entity.

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Proceeds from sale of investment in equity securities.

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

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

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

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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