Nature of Business and Summary of Significant Accounting Policies - Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Nature of Business and Summary of Significant Accounting Policies
Basic EPS	$ 3,615	$ 3,122	$ 10,420	$ 7,495
Weighted Average Shares, Basic EPS	18,472,000	18,489,000	18,476,000	18,607,000
Stock Options	44,000	44,000	54,000	47,000
Diluted EPS	$ 3,615	$ 3,122	$ 10,420	$ 7,495
Weighted Average Shares, Diluted EPS	18,516,000	18,533,000	18,530,000	18,654,000
Net Income Per Share, Basic	$ 0.20	$ 0.17	$ 0.56	$ 0.40
Net Income Per Share, Diluted	$ 0.20	$ 0.17	$ 0.56	$ 0.40