Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ / shares in Thousands, $ in Thousands	Dec. 31, 2021	Jun. 30, 2021
Allowance for doubtful accounts	$ 252	$ 311
Provision for obsolete inventory	$ 703	$ 679
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, authorized (in shares)	15,000,000	15,000,000
Common stock, issued (in shares)	3,939,180	3,913,055
Common stock, outstanding (in shares)	3,939,180	3,913,055