Common Stock and Common Stock Equivalents (Schedule of summarizes stock option activity) (Details) - $ / shares	12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2021
Common Stock and Common Stock Equivalents
Options outstanding at beginning of the year	28,000	28,000
Options granted	0	0
Options canceled or expired	0	0
Options outstanding at end of the year	28,000	28,000	28,000
Options exercisable at end of the year	22,250	15,500
Weighted average exercise price outstanding, at beginning of the year	$ 7.8	$ 7.8
Weighted average exercise price outstanding, at end of the year	7.8	7.8	$ 7.8
Weighted average exercise price exercisable at end of the year	$ 8.26	9
Weighted average remaining contractual term outstanding, at end of the year	4 years 9 months
Weighted average remaining contractual term outstanding, at end of the year	3 years 9 months
Range of exercise prices at end of the year, minimum		4.65	$ 4.65
Range of exercise prices at end of the year, maximum	$ 13.5	$ 13.5