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
	Sep. 30, 2019	Sep. 30, 2018
Numerator
Net income	$ 96	$ 2,559
Denominator
Basic weighted average common shares outstanding (in shares)	6,841,241	6,764,962
Dilutive effect of stock options and restricted stock (in shares)	144,000	200,000
Diluted weighted average common shares outstanding (in shares)	6,985,226	6,964,942
Basic net income per common share (in dollars per share)	$ 0.01	$ 0.38
Diluted net income per common share (in dollars per share)	$ 0.01	$ 0.37