Note A - Organization and Summary of Significant Accounting Policies - Calculation of Basic and Diluted Net Income Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Numerator
Net (loss) income	$ (1,645)	$ 6,541
Denominator
Basic weighted average common shares outstanding (in shares)	6,695,302	6,809,306
Dilutive effect of stock options and restricted stock shares (in shares)		289,000
Diluted weighted average common shares outstanding (in shares)	6,695,302	7,097,678
Basic net (loss) income per common share (in dollars per share)	$ (0.25)	$ 0.96
Diluted net (loss) income per common share (in dollars per share)	$ (0.25)	$ 0.92