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Stockholders' Equity (Narrative) (Details) - $ / shares	3 Months Ended	12 Months Ended
Stockholders' Equity (Narrative) (Details) - $ / shares	Sep. 30, 2020	Jun. 30, 2020	Jun. 30, 2019
Dividends Payable [Line Items]
Cash dividends on common stock (in dollars per share)		$ 1.00	$ 2.00
Anti-dilutive options excluded from calculation of EPS		276,712	196,039
Subsequent Event [Member]
Dividends Payable [Line Items]
Dividend payable, amount per share	$ 0.25
Dividend payable, date to be paid	Oct. 14, 2020
Dividend payable, date of record	Oct. 05, 2020
Special Dividend [Member]
Dividends Payable [Line Items]
Cash dividends on common stock (in dollars per share)			$ 1.00