CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($)	Jun. 30, 2016	Jun. 30, 2015
Allowance for doubtful accounts on trade receivables (in dollars)	$ 16,549	$ 16,296
Common stock, par value (in dollars per share)	$ 1	$ 1
Prior cumulative preferred stock, $5 par value: | Series A
Preferred stock, par value (in dollars per share)	$ 5	$ 5
Preferred stock, liquidation preference (in dollars)	$ 2,250,000	$ 2,220,000
Prior cumulative preferred stock, $5 par value: | Series B
Preferred stock, par value (in dollars per share)	$ 5	$ 5
Preferred stock, liquidation preference (in dollars)	$ 2,205,000	$ 2,175,000
Cumulative preferred stock, $20 par value | Series A
Preferred stock, par value (in dollars per share)	$ 20	$ 20
Preferred stock, liquidation preference (in dollars)	$ 5,077,730	$ 5,019,197
Cumulative preferred stock, $20 par value | Series B
Preferred stock, par value (in dollars per share)	$ 20	$ 20
Preferred stock, liquidation preference (in dollars)	$ 827,516	$ 817,977