Stock Options - Additional Information (Details) - USD ($)	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Stock Option
Proceeds from stock option exercises		$ 80,000	$ 53,000
2012 Employee Stock Option Plan
Stock Option
Outstanding (in shares)	214,080	235,680	145,000	114,400
Exercisable, end of period	98,176	70,000	67,600
Granted		141,880	58,000
Exercised	8,600	31,200	27,400
2012 Non-Employee Stock Option Plan
Stock Option
Outstanding (in shares)	12,000	24,000	20,400	55,600
Exercisable, end of period	6,240	11,520	6,000
Granted		3,600
Exercised	2,400		31,600
2018 Non-Employee Stock Option Plan
Stock Option
Outstanding (in shares)	70,100	96,800	30,400
Exercisable, end of period	29,960	24,480	4,800
Granted		66,400	40,000
Exercised	3,200		3,200
2020 Non-Employee Stock Option Plan
Stock Option
Stock-based compensation expense, allocated	$ 37,000
Outstanding (in shares)	10,000
Exercisable, end of period	2,000
Granted	10,000	0
Exercised	0	0
Fair Value	$ 12,000	$ 0