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, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Numerator
Net (loss) income	$ (1,318)	$ 2,466	$ 116	$ 4,956
Denominator
Basic weighted average common shares outstanding (in shares)	6,615,355	6,567,468	6,610,937	6,562,932
Dilutive effect of stock options (in shares)		116,000	226,000	102,000
Diluted weighted average common shares outstanding (in shares)	6,615,355	6,683,356	6,836,567	6,665,159
Basic net (loss) income per common share (in dollars per share)	$ (0.20)	$ 0.38	$ 0.02	$ 0.76
Diluted net (loss) income per common share (in dollars per share)	$ (0.20)	$ 0.37	$ 0.02	$ 0.74