Note 4 - Marketable Securities - Fair Value of Available for Sale Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Adjusted Cost	$ 37,726	$ 30,791
Unrealized Gains	24	10
Unrealized Losses	(2)	(1)
Fair Value	37,748	30,800
US Treasury Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Adjusted Cost	37,726	30,791
Unrealized Gains	24	10
Unrealized Losses	(2)	(1)
Fair Value	$ 37,748	$ 30,800