Stock Options - Reflects activity (Details) - USD ($)	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
2012 Employee Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, beginning of year	72,500	57,200
Granted	70,940	29,000
Terminated	(10,000)	0
Exercised	(15,600)	(13,700)
Outstanding, end of year	117,840	72,500
Exercisable, end of year	35,000	33,800
Weighted average fair value at grant date of options granted	$ 13.43	$ 9.15
Total intrinsic value of options exercised	$ 278,000	$ 160,000
Total intrinsic value of options outstanding	696,000	1,353,000
Total intrinsic value of options exercisable	$ 389,000	$ 731,000
Outstanding, beginning of year, weighted average exercise price	$ 11.01	$ 7.09
Granted, weighted average exercise price	24.50	16.59
Terminated/Lapsed, weighted average exercise price	19.84	0.00
Exercised, weighted average exercise price	7.55	6.42
Outstanding, end of period, weighted average exercise price	18.84	11.01
Exercisable, end of period, weighted average exercise price	$ 13.13	$ 8.05
2012 Non-Employee Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, beginning of year	10,200	27,800
Granted	1,800	0
Terminated		(1,800)
Exercised		(15,800)
Outstanding, end of year	12,000	10,200
Exercisable, end of year	5,760	3,000
Weighted average fair value at grant date of options granted	$ 12.94	$ 0.00
Total intrinsic value of options exercised		$ 192,000
Total intrinsic value of options outstanding	$ 157,000	221,000
Total intrinsic value of options exercisable	$ 87,000	$ 70,000
Outstanding, beginning of year, weighted average exercise price	$ 7.99	$ 6.85
Granted, weighted average exercise price	23.35	0.00
Terminated/Lapsed, weighted average exercise price		8.70
Exercised, weighted average exercise price		5.91
Outstanding, end of period, weighted average exercise price	10.29	7.99
Exercisable, end of period, weighted average exercise price	$ 8.35	$ 6.27
2018 Non-Employee Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, beginning of year	15,200	0
Granted	33,200	20,000
Terminated		(3,200)
Exercised		(1,600)
Outstanding, end of year	48,400	15,200
Exercisable, end of year	12,240	2,400
Weighted average fair value at grant date of options granted	$ 15.09	$ 10.24
Total intrinsic value of options exercised		$ 24,000
Total intrinsic value of options outstanding	$ 110,000	205,000
Total intrinsic value of options exercisable	$ 40,000	$ 32,000
Outstanding, beginning of year, weighted average exercise price	$ 16.20	$ 0.0
Granted, weighted average exercise price	26.82	16.2
Terminated/Lapsed, weighted average exercise price		16.2
Exercised, weighted average exercise price		16.2
Outstanding, end of period, weighted average exercise price	23.48	16.20
Exercisable, end of period, weighted average exercise price	$ 21.96	$ 16.2