Employee Benefits - Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding and Exercisable (Details)	12 Months Ended
	Jun. 30, 2020 $ / shares shares
50.2 mo.
Weighted Average Remaining Contractual Life	50 months 6 days
Options Outstanding, Number | shares	10,000
Options Outstanding, Weighted Average Exercise Price	$ 17.55
Options Exercisable, Number | shares	10,000
Options Exercisable, Weighted Average Exercise Price	$ 17.55
90.6 mo.
Weighted Average Remaining Contractual Life	90 months 18 days
Options Outstanding, Number | shares	13,500
Options Outstanding, Weighted Average Exercise Price	$ 37.31
Options Exercisable, Number | shares	5,400
Options Exercisable, Weighted Average Exercise Price	$ 37.31
102.2 mo.
Weighted Average Remaining Contractual Life	102 months 6 days
Options Outstanding, Number | shares	17,500
Options Outstanding, Weighted Average Exercise Price	$ 34.35
Options Exercisable, Number | shares	3,500
Options Exercisable, Weighted Average Exercise Price	$ 34.35
115.7 mo.
Weighted Average Remaining Contractual Life	115 months 21 days
Options Outstanding, Number | shares	19,500
Options Outstanding, Weighted Average Exercise Price	$ 37.40
Options Exercisable, Weighted Average Exercise Price	$ 37.40