Note A - Basis of Presentation and Summary of Significant Accounting Policies - Calculation of Basic and Diluted Net Income Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Numerator
Net income	$ 1,994	$ 2,051	$ 6,734	$ 2,167
Denominator
Basic weighted average common shares outstanding (in shares)	6,800,375	6,639,098	6,791,105	6,620,324
Dilutive effect of stock options and restricted stock (in shares)	595,000	270,000	321,000	241,000
Diluted weighted average common shares outstanding (in shares)	7,394,600	6,909,475	7,119,589	6,860,870
Basic net income per common share (in dollars per share)	$ 0.29	$ 0.31	$ 0.99	$ 0.33
Diluted net income per common share (in dollars per share)	$ 0.27	$ 0.30	$ 0.95	$ 0.32