Note 3 - Investment Securities (Details Textual) $ in Thousands	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss	$ 1,100	$ 993
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Excluding Accrued Interest	$ 5	$ 5
Debt Securities Available For Sale Total Number Of Positions	159	161
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	153	157
Debt Securities, Available-for-Sale, Term (Year)	3 years 2 months 12 days
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	$ 0
Debt Securities, Available-for-Sale, Excluding Accrued Interest	$ 255,891	$ 258,327
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Other Assets	Other Assets
Excluding Holdings in U.S. Treasury securities and U.S. Government Agencies [Member]
Investments Exceeding Ten Percent of Equity	0
Asset Pledged as Collateral [Member] \| Deposits [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	$ 135,700	$ 116,200

The total number of positions for available for sale debt securities.

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The number of investments exceeding ten percent of equity.

+ References

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Amount, after allowance for credit loss, of accrued interest 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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Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, 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 excluding accrued interest, of allowance for credit loss 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 excluding accrued interest, 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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Period between issuance and maturity of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

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