Note 5 - Marketable Securities - Marketable Securities (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Amortized Cost	$ 151,965
Unrealized Gains	64
Unrealized Losses	(366)
Fair Value	151,663
Corporate Debt Securities [Member]
Amortized Cost	87,998
Unrealized Gains	12
Unrealized Losses	(250)
Fair Value	87,760
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Amortized Cost	37,680
Unrealized Gains	33
Unrealized Losses	(31)
Fair Value	37,682
Certificates of Deposit [Member]
Amortized Cost	19,689
Unrealized Gains	16
Unrealized Losses	(38)
Fair Value	19,667
Asset-Backed Securities [Member]
Amortized Cost	6,598
Unrealized Gains	3
Unrealized Losses	(47)
Fair Value	$ 6,554

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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