Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2021	Jun. 30, 2021
Allowance for doubtful accounts	$ 602	$ 665
Common stock, par value (in dollars per share)	$ 1	$ 1
Class A Common Shares
Common stock, shares authorized (in shares)	20,000,000	20,000,000
Common stock, shares, outstanding (in shares)	6,644,107	6,475,307
Class B Common Shares
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	10,000,000	10,000,000
Common stock, shares, outstanding (in shares)	607,748	633,505