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, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Numerator
Net income	$ 2,051	$ 745	$ 2,167	$ 5,701
Denominator
Basic weighted average common shares outstanding (in shares)	6,639,098	6,581,632	6,620,324	6,569,165
Dilutive effect of stock options and restricted stock (in shares)	270,000	32,000	241,000	79,000
Diluted weighted average common shares outstanding (in shares)	6,909,475	6,613,955	6,860,870	6,648,091
Basic net income per common share (in dollars per share)	$ 0.31	$ 0.11	$ 0.33	$ 0.87
Diluted net income per common share (in dollars per share)	$ 0.30	$ 0.11	$ 0.32	$ 0.86