Note 10 - Investments in Marketable Securities - Amortized Cost and Estimated Fair Value of Debt Securities as Available for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Within 1 year, cost	$ 34,236	$ 32,718
Within 1 year, fair value	34,159	32,843
1 to 5 years, cost	89,482	95,293
1 to 5 years, fair value	87,771	96,937
6 to 10 years, cost	43,491	41,580
6 to 10 years, fair value	40,858	41,835
Over 10 years, cost	0	496
Over 10 years, fair value	0	485
Cost	167,209	170,087
Fair Value	$ 162,788	$ 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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