Note 3 - Marketable Securities - Marketable Securities (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Amortized Cost	$ 104,762
Unrealized Gains	0
Unrealized Losses	(641)
Total	104,121
Corporate Debt Securities [Member]
Amortized Cost	70,058
Unrealized Gains	0
Unrealized Losses	(506)
Total	69,552
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Amortized Cost	20,825
Unrealized Gains	0
Unrealized Losses	(50)
Total	20,775
Certificates of Deposit [Member]
Amortized Cost	7,487
Unrealized Gains	0
Unrealized Losses	(39)
Total	7,448
Asset-Backed Securities [Member]
Amortized Cost	6,392
Unrealized Gains	0
Unrealized Losses	(46)
Total	$ 6,346

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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