Note 10 - Investments in Marketable Securities - Amortized Cost and Estimated Fair Value of Debt Securities as Available for Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Within 1 year, cost	$ 33,703	$ 32,718
Within 1 year, fair value	33,385	32,843
1 to 5 years, cost	87,303	95,293
1 to 5 years, fair value	83,858	96,937
6 to 10 years, cost	43,080	41,580
6 to 10 years, fair value	38,728	41,835
Over 10 years, cost	0	496
Over 10 years, fair value	0	485
Cost	164,086	170,087
Fair Value	$ 155,971	$ 172,100

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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