Note 8 - Marketable Securities - Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Amortized Cost	$ 5,194	$ 5,113
Estimated Fair Value	5,305	$ 5,230
Corporate and Municipal Debt Securities [Member]
Amortized Cost	5,194
Unrealized Gain	115
Unrealized Loss	(4)
Estimated Fair Value	$ 5,305

Amount 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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+ Details