Stock Options - Activity (Details) - USD ($)	3 Months Ended	15 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025
Options
Exercised	(18,000)
2012 Employee Stock Option Plan
Options
Outstanding, beginning of year	361,036	363,036	363,036
Forfeited/Lapsed	(6,000)
Exercised	(18,000)	(2,000)
Outstanding, end of period	337,036	361,036	337,036
Exercisable, end of period	267,136	198,060	267,136
Weighted average exercise price
Weighted average exercise price, beginning of year	$ 21.44	$ 21.47	$ 21.47
Forfeited/Lapsed (per share)	(22.5)
Exercised (per share)	(22.99)	(26.94)
Weighted average exercise price, end of period	21.33	21.44	21.33
Exercisable, end of period, weighted average exercise price	$ 20.9	$ 20.97	$ 20.9
Additional disclosures
Total intrinsic value of options exercised	$ 325,000	$ 35,000
Total intrinsic value of options outstanding	7,286,000	6,869,000	$ 7,286,000
Total intrinsic value of options exercisable	$ 5,890,000	$ 3,860,000	$ 5,890,000
2012 Non-Employee Stock Option Plan
Options
Outstanding, beginning of year	20,400	20,400	20,400
Exercised	0	0
Outstanding, end of period	20,400	20,400	20,400
Exercisable, end of period	18,480	16,560	18,480
Weighted average exercise price
Weighted average exercise price, beginning of year	$ 14.39	$ 14.39	$ 14.39
Weighted average exercise price, end of period	14.39	14.39	14.39
Exercisable, end of period, weighted average exercise price	$ 13.5	$ 12.41	$ 13.5
Additional disclosures
Total intrinsic value of options outstanding	$ 583,000	$ 532,000	$ 583,000
Total intrinsic value of options exercisable	$ 544,000	$ 465,000	$ 544,000
2018 Non-Employee Stock Option Plan
Options
Outstanding, beginning of year	64,900	68,900	68,900
Granted	0	0
Forfeited/Lapsed		(4,000)
Exercised	0	0
Outstanding, end of period	64,900	64,900	64,900
Exercisable, end of period	62,200	59,500	62,200
Weighted average exercise price
Weighted average exercise price, beginning of year	$ 14.02	$ 14.54	$ 14.54
Forfeited/Lapsed (per share)		(22.93)
Weighted average exercise price, end of period	14.02	14.02	14.02
Exercisable, end of period, weighted average exercise price	$ 13.63	$ 13.21	$ 13.63
Additional disclosures
Total intrinsic value of options outstanding	$ 1,877,000	$ 1,716,000	$ 1,877,000
Total intrinsic value of options exercisable	$ 1,823,000	$ 1,621,000	$ 1,823,000
2020 Non-Employee Stock Option Plan
Options
Outstanding, beginning of year	51,900	56,900	56,900
Granted	0	0
Forfeited/Lapsed		(2,000)
Exercised	0	(3,000)
Outstanding, end of period	51,900	51,900	51,900
Exercisable, end of period	42,520	34,140	42,520
Weighted average exercise price
Weighted average exercise price, beginning of year	$ 23	$ 23.35	$ 23.35
Forfeited/Lapsed (per share)		(26.94)
Exercised (per share)		(26.94)
Weighted average exercise price, end of period	23	23	23
Exercisable, end of period, weighted average exercise price	$ 22.28	$ 21.42	$ 22.28
Additional disclosures
Total intrinsic value of options exercised		$ 32,000
Total intrinsic value of options outstanding	$ 1,035,000	906,000	$ 1,035,000
Total intrinsic value of options exercisable	$ 879,000	$ 650,000	$ 879,000
2022 Employee Stock Option Plan
Options
Outstanding, beginning of year	130,000	130,000	130,000
Granted	0	0
Exercised			0
Outstanding, end of period	130,000	130,000	130,000
Exercisable, end of period	52,000	26,000	52,000
Weighted average exercise price
Weighted average exercise price, beginning of year	$ 41.38	$ 41.38	$ 41.38
Weighted average exercise price, end of period	41.38	41.38	41.38
Exercisable, end of period, weighted average exercise price	$ 41.38	$ 41.38	$ 41.38
Additional disclosures
Total intrinsic value of options outstanding	$ 334,000	$ 189,000	$ 334,000
Total intrinsic value of options exercisable	$ 133,000	$ 38,000	$ 133,000

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