Shareholders' Equity - Class A Common Stock Options Outstanding and Exercisable Under the Employee Stock Option Plans (Details) - $ / shares	12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Shares	22,000	22,000	29,000	29,000
Options Outstanding, Remaining Life in Years	2 years 5 months 9 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 18.72	$ 18.72	$ 17.03	$ 17.03
Options Exercisable, Shares	22,000
Options Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 18.72
October 3, 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Date of Option Grant	Oct. 03, 2007
Options Outstanding, Shares	20,000
Options Outstanding, Remaining Life in Years	2 years 3 months
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 19.36
Options Exercisable, Shares	20,000
Options Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 19.36
October 7, 2009 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Date of Option Grant	Oct. 07, 2009
Options Outstanding, Shares	2,000
Options Outstanding, Remaining Life in Years	4 years 3 months 7 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 12.31
Options Exercisable, Shares	2,000
Options Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 12.31