Note 8 - Marketable Securities - Short-term and Long-term Available for Sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Amortized Cost	$ 51,366	$ 26,039
Unrealized Gains	0	7
Unrealized Losses	(1,379)	(126)
Fair Value	49,987	25,920
US Government Agencies Debt Securities [Member]
Amortized Cost	25,275	2,500
Unrealized Gains	0	0
Unrealized Losses	(750)	(12)
Fair Value	24,525	2,488
Corporate Debt Securities [Member]
Amortized Cost	9,578	9,303
Unrealized Gains	0	0
Unrealized Losses	(205)	(44)
Fair Value	9,373	9,259
US States and Political Subdivisions Debt Securities [Member]
Amortized Cost	15,574	12,549
Unrealized Gains	0	0
Unrealized Losses	(417)	(70)
Fair Value	15,157	12,479
Bank Time Deposits [Member]
Amortized Cost	939	1,687
Unrealized Gains	0	7
Unrealized Losses	(7)	0
Fair Value	$ 932	$ 1,694

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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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