Note 9 - Net Income Per Share - Computation of Basic and Diluted Net Income per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Net income	$ 11,141	$ 11,826	$ 9,887	$ 7,502	$ 8,098	$ 6,040	$ 32,854	$ 21,640
Basic (in shares)	22,476			22,263			22,433	22,196
Basic earnings per share (in dollars per share)	$ 0.5			$ 0.34			$ 1.46	$ 0.97
Common stock equivalents, if dilutive (in shares)	360			218			290	215
Shares used in computing diluted earnings per common share (in shares)	22,836			22,481			22,723	22,411
Diluted earnings per share (in dollars per share)	$ 0.49			$ 0.33			$ 1.45	$ 0.97
Shares excluded in computing diluted earnings per share as those shares would be anti-dilutive (in shares)	0			192			24	286