Note 3 - U.S. Treasury Securities, Available-for-sale (Details Textual) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale	$ 99,467	$ 148,820
US Treasury Securities [Member]
Debt Securities, Available-for-Sale	$ 99,467	$ 148,820

Amount 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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+ Details