Note 3 - Marketable Securities - Marketable Securities (Details) $ in Thousands	Jun. 30, 2022 USD ($)
Amortized Cost	$ 106,292
Unrealized Gains	0
Unrealized Losses	(512)
Total	105,780
Corporate Debt Securities [Member]
Amortized Cost	73,184
Unrealized Gains	0
Unrealized Losses	(416)
Total	72,768
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Amortized Cost	22,713
Unrealized Gains	0
Unrealized Losses	(52)
Total	22,661
Certificates of Deposit [Member]
Amortized Cost	5,674
Unrealized Gains	0
Unrealized Losses	(20)
Total	5,654
Asset-Backed Securities [Member]
Amortized Cost	4,721
Unrealized Gains	0
Unrealized Losses	(24)
Total	$ 4,697

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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