Note 2 - Debt Securities (Details Textual) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax	$ (1,300)	$ 234
OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, Tax	(513)	94
Proceeds from Sale and Maturity of Debt Securities, Available-for-Sale	0	0
Debt Securities, Available-for-Sale, Transfer to Trading, Gain (Loss)	0	$ 0
Debt Securities, Unrealized Loss, Credit Impairment	0		$ 0
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0		0
Debt Securities, Available-for-Sale, Excluding Accrued Interest	210,583		218,160
Asset Pledged as Collateral [Member] \| Letter of Credit [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	9,400		8,900
Asset Pledged as Collateral [Member] \| Deposits [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	$ 0		$ 0

The credit impairment on debt securities in an unrealized loss position.

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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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Amount of unrealized gain (loss) recognized in earnings from transfer of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) to investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

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Amount, after tax and before adjustment, of unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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Amount of cash inflow from sale, maturity, prepayment and call 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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