NOTE 5 - EARNINGS PER SHARE - Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
EARNINGS PER SHARE
Net income	$ 11,228	$ 12,918
Basic EPS	$ 0.71	$ 0.82
Diluted EPS	$ 0.70	$ 0.81
Weighted average common shares outstanding (in shares)	15,796,796	15,693,345
Weighted average common shares issuable upon exercise of stock options and under the employee stock purchase plan (in shares)	214,660	229,595
Weighted average common and common equivalent shares outstanding (in shares)	16,011,456	15,922,940