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		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Numerator
Net income	$ 3,632	$ 476	$ 5,890	$ 572
Denominator
Basic weighted average common shares outstanding (in shares)	6,270,419	6,795,269	6,344,256	6,818,249
Dilutive effect of stock options and restricted stock (in shares)	135,000	91,000	94,000	117,000
Diluted weighted average common shares outstanding (in shares)	6,405,308	6,885,934	6,438,143	6,935,580
Basic net income per common share (in dollars per share)	$ 0.58	$ 0.07	$ 0.93	$ 0.08
Diluted net income per common share (in dollars per share)	$ 0.57	$ 0.07	$ 0.91	$ 0.08