Note 9 - Investments in Marketable Securities - Amortized Cost and Estimated Fair Value of Debt Securities as Available for Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Within 1 year, cost	$ 25,707	$ 19,664
Within 1 year, fair value	25,317	19,328
1 to 5 years, cost	66,117	81,517
1 to 5 years, fair value	63,379	77,118
6 to 10 years, cost	32,648	33,515
6 to 10 years, fair value	30,606	30,802
Over 10 years, cost	646	642
Over 10 years, fair value	502	479
Cost	125,118	135,338
Fair Value	$ 119,804	$ 127,727

Amortized cost 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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