Note 7 - Marketable Securities - Summary of Gross Unrealized Losses and Fair Values on Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Less than 12 months, Fair value	$ 37,893	$ 18,193
Less than 12 months, Gross unrealized loss	237	49
12 months or greater, Fair value	73,923	86,643
12 months or greater, Gross unrealized loss	$ 3,148	$ 3,928

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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