Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2023	Jun. 30, 2022
Accounts receivable, allowance for doubtful accounts	$ 23	$ 3,383
Preferred stock par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	500,000	500,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	20,000,000	20,000,000
Common stock, shares issued (in shares)	6,073,813	6,129,611
Common stock, shares outstanding (in shares)	6,073,813	6,129,611
Treasury stock, shares (in shares)	3,240,593	3,061,795