Stock Option - Activity (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023	Jun. 30, 2023
2012 Employee Stock Option Plan
Options
Outstanding, beginning of year			521,580	523,080	523,080
Granted	0	0	0	37,500
Forfeited/Lapsed			(11,000)
Exercised	(115,944)	(30,800)	(147,544)	(38,000)
Outstanding, end of period	363,036	522,580	363,036	522,580	521,580
Exercisable, end of period	178,984	236,652	178,984	236,652
Weighted average exercise price
Weighted average exercise price, beginning of year			$ 19.37	$ 18.59	$ 18.59
Granted (per share)				26.94
Forfeited/Lapsed (per share)			3.15
Exercised (per share)			15.43	10.63
Weighted average exercise price, end of period	$ 21.47	$ 19.34	21.47	19.34	$ 19.37
Exercisable, end of period, weighted average exercise price	$ 21.59	$ 17.47	$ 21.59	17.47
Additional disclosures
Weighted average fair value at grant date of options granted				$ 13.36
Total intrinsic value of options exercised			$ 3,972,000	$ 787,000
Total intrinsic value of options outstanding	$ 6,787,000	$ 9,531,000	6,787,000	9,531,000
Total intrinsic value of options exercisable	$ 3,323,000	$ 4,760,000	$ 3,323,000	$ 4,760,000
2012 Non-Employee Stock Option Plan
Options
Outstanding, beginning of year			20,400	20,400	20,400
Granted	0	0	0	0
Exercised	0	0	0	0
Outstanding, end of period	20,400	20,400	20,400	20,400	20,400
Exercisable, end of period	16,560	13,920	16,560	13,920
Weighted average exercise price
Weighted average exercise price, beginning of year			$ 14.39	$ 14.39	$ 14.39
Exercised (per share)			0
Weighted average exercise price, end of period	$ 14.39	$ 14.39	14.39	14.39	$ 14.39
Exercisable, end of period, weighted average exercise price	$ 12.41	$ 10.99	$ 12.41	$ 10.99
Additional disclosures
Total intrinsic value of options outstanding	$ 526,000	$ 473,000	$ 526,000	$ 473,000
Total intrinsic value of options exercisable	$ 460,000	$ 370,000	$ 460,000	$ 370,000
2018 Non-Employee Stock Option Plan
Options
Outstanding, beginning of year			75,000	89,000	89,000
Granted	0	0	0	0
Exercised	(1,500)	(1,600)	(3,100)	(11,500)
Outstanding, end of period	71,900	77,500	71,900	77,500	75,000
Exercisable, end of period	62,500	53,220	62,500	53,220
Weighted average exercise price
Weighted average exercise price, beginning of year			$ 14.83	$ 14.91	$ 14.91
Exercised (per share)			18.98	15.14
Weighted average exercise price, end of period	$ 14.65	$ 14.88	14.65	14.88	$ 14.83
Exercisable, end of period, weighted average exercise price	$ 13.41	$ 13.03	$ 13.41	$ 13.03
Additional disclosures
Total intrinsic value of options exercised			$ 59,000	$ 164,000
Total intrinsic value of options outstanding	$ 1,834,000	$ 1,760,000	1,834,000	1,760,000
Total intrinsic value of options exercisable	$ 1,672,000	$ 1,307,000	$ 1,672,000	$ 1,307,000
2020 Non-Employee Stock Option Plan
Options
Outstanding, beginning of year			56,900	26,900	26,900
Granted	0	5,000	0	30,000
Exercised	0	0	0	0
Outstanding, end of period	56,900	56,900	56,900	56,900	56,900
Exercisable, end of period	30,140	18,760	30,140	18,760
Weighted average exercise price
Weighted average exercise price, beginning of year			$ 23.35	$ 18.64	$ 18.64
Granted (per share)				27.57
Weighted average exercise price, end of period	$ 23.35	$ 23.35	23.35	23.35	$ 23.35
Exercisable, end of period, weighted average exercise price	$ 21.72	$ 20.73	$ 21.72	20.73
Additional disclosures
Weighted average fair value at grant date of options granted				$ 13.74
Total intrinsic value of options outstanding	$ 957,000	$ 810,000	$ 957,000	$ 810,000
Total intrinsic value of options exercisable	$ 556,000	$ 316,000	$ 556,000	$ 316,000
2022 Employee Stock Option Plan
Options
Outstanding, beginning of year			5,000
Granted	0	0	10,000
Forfeited/Lapsed			(5,000)
Exercised	0		0
Outstanding, end of period	10,000		10,000		5,000
Exercisable, end of period	2,000		2,000
Weighted average exercise price
Weighted average exercise price, beginning of year			$ 40.01
Granted (per share)			21.60
Forfeited/Lapsed (per share)			40.01
Weighted average exercise price, end of period	$ 21.60		21.60		$ 40.01
Exercisable, end of period, weighted average exercise price	$ 21.60		21.60
Additional disclosures
Weighted average fair value at grant date of options granted			$ 9.75
Total intrinsic value of options outstanding	$ 186,000		$ 186,000
Total intrinsic value of options exercisable	$ 37,000		$ 37,000