Note 4 - Marketable Securities - Fair Value of Marketable Securities (Details) - Fair Value, Recurring [Member] - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Total marketable securities	$ 34,731	$ 41,122
Fair Value, Inputs, Level 1 [Member]
Total marketable securities	0	0
Fair Value, Inputs, Level 2 [Member]
Total marketable securities	34,731	41,122
Fair Value, Inputs, Level 3 [Member]
Total marketable securities	0	0
Commercial Paper and Corporate Bonds [Member]
Total marketable securities	25,816	28,291
Commercial Paper and Corporate Bonds [Member] \| Fair Value, Inputs, Level 1 [Member]
Total marketable securities	0	0
Commercial Paper and Corporate Bonds [Member] \| Fair Value, Inputs, Level 2 [Member]
Total marketable securities	25,816	28,291
Commercial Paper and Corporate Bonds [Member] \| Fair Value, Inputs, Level 3 [Member]
Total marketable securities	0	0
US Government Agencies Debt Securities [Member]
Total marketable securities	8,915	12,831
US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Total marketable securities	0	0
US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Total marketable securities	8,915	12,831
US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Total marketable securities	$ 0	$ 0

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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+ Details