Stock Option - Activity (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Jun. 30, 2022
2012 Employee Stock Option Plan
Options
Outstanding, beginning of year			523,080	214,080	214,080
Granted	0	0	37,500	338,000
Exercised	(30,800)	(1,000)	(38,000)	(29,000)
Outstanding, end of period	522,580	523,080	522,580	523,080	523,080
Exercisable, end of period	236,652	164,776	236,652	164,776
Weighted average exercise price
Weighted average exercise price, beginning of year			$ 18.59	$ 9.59	$ 9.59
Granted (per share)			26.94	23.17
Exercised (per share)			10.63	5.45
Weighted average exercise price, end of period	$ 19.34	$ 18.59	19.34	18.59	$ 18.59
Exercisable, end of period, weighted average exercise price	$ 17.47	$ 15.01	17.47	15.01
Additional disclosures
Weighted average fair value at grant date of options granted			$ 13.36	$ 12.16
Total intrinsic value of options exercised			$ 787,000	$ 502,000
Total intrinsic value of options outstanding	$ 9,531,000	$ 1,903,000	9,531,000	1,903,000
Total intrinsic value of options exercisable	$ 4,760,000	$ 1,085,000	$ 4,760,000	$ 1,085,000
2012 Non-Employee Stock Option Plan
Options
Outstanding, beginning of year			20,400	12,000	12,000
Granted	0	0	0	9,600
Outstanding, end of period	20,400	21,600	20,400	21,600	20,400
Exercisable, end of period	13,920	12,480	13,920	12,480
Weighted average exercise price
Weighted average exercise price, beginning of year			$ 14.39	$ 6.55	$ 6.55
Granted (per share)				22.93
Exercised (per share)			0
Weighted average exercise price, end of period	$ 14.39	$ 13.83	14.39	13.83	$ 14.39
Exercisable, end of period, weighted average exercise price	$ 10.99	$ 8.48	$ 10.99	8.48
Additional disclosures
Weighted average fair value at grant date of options granted				$ 12.58
Total intrinsic value of options outstanding	$ 473,000	$ 168,000	$ 473,000	$ 168,000
Total intrinsic value of options exercisable	$ 370,000	$ 155,000	$ 370,000	$ 155,000
2018 Non-Employee Stock Option Plan
Options
Outstanding, beginning of year			89,000	70,100	70,100
Granted	0	0	0	23,500
Exercised	(1,600)	(1,600)	(11,500)	(4,600)
Outstanding, end of period	77,500	89,000	77,500	89,000	89,000
Exercisable, end of period	53,220	45,040	53,220	45,040
Weighted average exercise price
Weighted average exercise price, beginning of year			$ 14.91	$ 11.93	$ 11.93
Granted (per share)				22.93
Exercised (per share)			15.14	10.43
Weighted average exercise price, end of period	$ 14.88	$ 14.91	14.88	14.91	$ 14.91
Exercisable, end of period, weighted average exercise price	$ 13.03	$ 12.98	$ 13.03	12.98
Additional disclosures
Weighted average fair value at grant date of options granted				$ 12.58
Total intrinsic value of options exercised			$ 164,000	$ 58,000
Total intrinsic value of options outstanding	$ 1,760,000	$ 556,000	1,760,000	556,000
Total intrinsic value of options exercisable	$ 1,307,000	$ 351,000	$ 1,307,000	$ 351,000
2020 Non-Employee Stock Option Plan
Options
Outstanding, beginning of year			26,900	10,000	10,000
Granted	5,000	0	30,000	16,900
Outstanding, end of period	56,900	26,900	56,900	26,900	26,900
Exercisable, end of period	18,760	7,380	18,760	7,380
Weighted average exercise price
Weighted average exercise price, beginning of year			$ 18.64	$ 11.40	$ 11.40
Granted (per share)			27.57	22.93
Weighted average exercise price, end of period	$ 23.35	$ 18.64	23.35	18.64	$ 18.64
Exercisable, end of period, weighted average exercise price	$ 20.73	$ 16.68	20.73	16.68
Additional disclosures
Weighted average fair value at grant date of options granted			$ 13.74	$ 12.58
Total intrinsic value of options outstanding	$ 810,000	$ 91,000	$ 810,000	$ 91,000
Total intrinsic value of options exercisable	$ 316,000	$ 36,000	$ 316,000	$ 36,000