Note 5 - Marketable Securities - Marketable Securities (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Debt Securities, Available-for-Sale, Amortized Cost	$ 4,950
Debt Securities, Available-for-Sale	4,973
Corporate Debt Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost	4,950
Debt Securities, Available-for-Sale, Gross Unrealized Gains	26
Debt Securities, Available-for-Sale, Gross Unrealized Losses	(3)
Debt Securities, Available-for-Sale	$ 4,973

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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Amortized cost 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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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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