Note 6 - Investment Securities (Details Textual)	3 Months Ended
Mar. 31, 2023 USD ($) Security	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Investment Securities [Line Items]
Proceeds from sale of investment securities	$ 9,081,000	$ 0
Available-for-sale securities pledged as collateral	$ 283,019,000		$ 237,645,000
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	629,187,000		$ 649,217,000
Available-for-sale	537,904,000		546,525,000
Investment equity securities	11,908,000		$ 12,056,000
Proceeds from sale of investment equity securities	$ 709,000	262,000
Pooled Trust Preferred Security [Member]
Investment Securities [Line Items]
Number of trust preferred securities \| Security	1
Available-for-sale, amortized cost	$ 61,000
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	44,000	(8,000)
Debt Securities [Member]
Investment Securities [Line Items]
Income tax expense (benefit) related to net realized gains (losses) on sales of securities	$ 54,000	$ 0

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.

+ References

No definition available.

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- Definition

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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Indicates type of restriction on 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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This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

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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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