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	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Numerator
Net income (loss)	$ 10,768	$ (1,645)
Denominator
Basic weighted average common shares outstanding (in shares)	6,290,689	6,695,302
Dilutive effect of stock options and restricted stock shares (in shares)	88,000
Diluted weighted average common shares outstanding (in shares)	6,379,486	6,695,302
Basic net income (loss) per common share (in dollars per share)	$ 1.71	$ (0.25)
Diluted net income (loss) per common share (in dollars per share)	$ 1.69	$ (0.25)