Note 2 - Debt Securities (Details Textual) $ in Thousands	9 Months Ended
Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	$ 0		$ 0
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss	$ 926		$ 694
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	82		103
Percentage of Combined Depreciation of Combined Reported Value of Aggregate Securities Portfolio	8.48%		8.74%
Proceeds from Sale of Debt Securities, Available-for-Sale	$ 0	$ 0
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	$ 142,206		$ 184,687
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Interest Receivable		Interest Receivable
Asset Pledged as Collateral [Member]
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	$ 28,650		$ 24,640

Represents the percentage of combined depreciation of combined reported value of aggregate securities portfolio.

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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).

+ References

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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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Amortized cost excluding accrued interest, before allowance for credit loss, 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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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 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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