CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Jun. 30, 2020	Jun. 30, 2019
Allowance for doubtful accounts	$ 1,796,000	$ 1,324,000
Preferred stock, par value (in US$ per share)	$ 1	$ 1
Preferred stock, shares authorized (in shares)	500,000	500,000
Liquidation Preference	$ 16,178	$ 15,624
Common stock, par value (in US$ per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	25,000,000	25,000,000
Common stock, shares issued (in shares)	17,347,774	17,042,132
Common stock, shares outstanding (in shares)	17,347,774	17,042,132
Cumulative Preferred Stock [Member]
Preferred stock, shares authorized (in shares)	21,000	21,000
Preferred stock, issued (in shares)	14,700	14,700
Preferred Stock, outstanding (in shares)	14,700	14,700