Note 3 - Investments in Debt Securities - Amortized Cost to Fair Value of Debt Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Amortized cost	$ 120	$ 2,687
Unrealized gains	2	5
Fair value	$ 122	$ 2,692

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

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+ Details