Note 2 - Summary of Significant Accounting Policies - Amortized Cost to Fair Value of HTM Debt Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Amortized cost	$ 19,349	$ 21,059
Gross unrecognized gains	59	50
Gross unrecognized losses	(12)	(33)
Fair value	$ 19,396	$ 21,076

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

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+ Details