Note 10 - Investments in Marketable Securities - Amortized Cost and Estimated Fair Value of Debt Securities as Available for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Within 1 year, cost	$ 24,509	$ 19,664
Within 1 year, fair value	24,023	19,328
1 to 5 years, cost	71,047	81,517
1 to 5 years, fair value	69,082	77,118
6 to 10 years, cost	31,197	33,515
6 to 10 years, fair value	30,499	30,802
Over 10 years, cost	307	642
Over 10 years, fair value	307	479
Cost	127,060	135,338
Fair Value	$ 123,911	$ 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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