Note 3 - Investment Securities - Schedule of Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Amortized cost, as adjusted	$ 130,626	$ 120,363
Gross unrealized holding gains	95	331
Gross unrealized holding losses	(142)	0
Estimated fair value	130,579	120,694
US Government Agencies Debt Securities [Member] \| Short-Term Investments [Member]
Amortized cost, as adjusted	72,221	62,822
Gross unrealized holding gains	63	130
Gross unrealized holding losses	(11)	0
Estimated fair value	72,273	62,952
US Government Agencies Debt Securities [Member] \| Long Term Investments [Member]
Amortized cost, as adjusted	58,405	57,541
Gross unrealized holding gains	32	201
Gross unrealized holding losses	(131)	0
Estimated fair value	$ 58,306	$ 57,742

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

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+ Details

- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

+ References

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+ Details