Note 6 - EARNINGS PER SHARE - Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
EARNINGS PER SHARE
Net income	$ 27,157	$ 23,624
Basic EPS	$ 1.62	$ 1.51
Diluted EPS	$ 1.60	$ 1.49
Weighted average common shares outstanding	16,776,289	15,625,112
Weighted average common shares issuable upon exercise of stock options and under the employee stock purchase plan (in shares)	165,843	227,144
Weighted average common and common equivalent shares outstanding	16,942,132	15,852,256