Note 1 - Summary of Significant Accounting Policies - Net Income Per Share Computation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Net income	$ 24,783	$ 30,971	$ 31,800
Allocation of distributed and undistributed income to unvested restricted stock shareholders	(2)	(8)	(16)
Net income attributable to common shareholders	$ 24,781	$ 30,963	$ 31,784
Weighted average common shares outstanding – basic (in shares)	23,703	24,540	24,922
Net income per share – basic (in dollars per share)	$ 1.05	$ 1.26	$ 1.28
Weighted average effect of dilutive securities – stock options (in shares)	40	133	130
Denominator for diluted earnings per share – adjusted weighted average shares (in shares)	23,743	24,673	25,052
Net income per share – diluted (in dollars per share)	$ 1.04	$ 1.25	$ 1.27