Note 9 - Fair Value Measurements - Financial Assets and Liabilities Measured on a Recurring Basis (Details) - Fair Value, Recurring [Member] - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Money market funds	$ 222,478	$ 282,121
Equity securities	7,830	49,655
Common stock options	3	3
Total assets	230,311	331,779
Forward contracts	262
Total liabilities	262
Fair Value, Inputs, Level 1 [Member]
Money market funds	222,478	282,121
Equity securities	7,830	49,655
Common stock options	0	0
Total assets	230,308	331,776
Forward contracts	0
Total liabilities	0
Fair Value, Inputs, Level 2 [Member]
Money market funds	0	0
Equity securities	0	0
Common stock options	3	3
Total assets	3	3
Forward contracts	262
Total liabilities	262
Fair Value, Inputs, Level 3 [Member]
Money market funds	0	0
Equity securities	0	0
Common stock options	0	0
Total assets	0	$ 0
Forward contracts	0
Total liabilities	$ 0