Note 8 - Earnings Per Share - Reconciliation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net earnings used in the computation of basic and diluted earnings per share (in thousands)	$ 2,376	$ 2,450
Weighted average shares outstanding - basic (in shares)	14,927,341	14,821,659
Common stock equivalents (in shares)	335,313	635,970
(Diluted) (in shares)	15,262,654	15,457,629
Net earnings (in dollars per share)	$ 0.16	$ 0.17
Net earnings (in dollars per share)	$ 0.16	$ 0.16