Note 6 - Marketable Securities - Summary of Gross Unrealized Losses and Fair Values on Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Less than 12 months, Fair value	$ 18,905	$ 58,706
Less than 12 months, Gross unrealized loss	(268)	(1,885)
12 months or greater, Fair value	77,534	48,539
12 months or greater, Gross unrealized loss	$ (5,771)	$ (4,980)

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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