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Stockholders' Equity (Narrative) (Details) - $ / shares	3 Months Ended	12 Months Ended
Stockholders' Equity (Narrative) (Details) - $ / shares	Sep. 30, 2019	Jun. 30, 2019	Jun. 30, 2018
Dividends Payable [Line Items]
Cash dividends on common stock (in dollars per share)		$ 2.00	$ 1.00
Anti-dilutive options excluded from calculation of EPS		196,039	2,500
Subsequent Event [Member]
Dividends Payable [Line Items]
Dividend payable, amount per share	$ 0.25
Dividend payable, date to be paid	Sep. 27, 2019
Dividend payable, date of record	Sep. 20, 2019
Special Dividend [Member]
Dividends Payable [Line Items]
Dividend payable, amount per share		$ 1.00