Note 2 - Investments in Bond Securities - Amortized Cost to Fair Value of Debt Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Amortized cost	$ 2,687	$ 3,135
Unrealized gains	5	4
Fair value	$ 2,692	$ 3,139

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Period Type:	instant