Note 6 - Marketable Securities - Summary of Gross Unrealized Losses and Fair Values on Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Less than 12 months, Fair value	$ 24,160	$ 28,762
Less than 12 months, Gross unrealized loss	97	160
12 months or greater, Fair value	37,121	61,996
12 months or greater, Gross unrealized loss	$ 1,118	$ 1,589

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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