Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2019	Jun. 30, 2019
Accounts receivable, allowance for doubtful accounts	$ 60	$ 25
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 outstanding (in shares)	7,208,355	7,225,072
Treasury stock, shares (in shares)	1,643,322	1,626,605