Investments and Derivative Instruments - Gross Unrealized Losses (Details) (Preferred Stock, USD $)	Mar. 31, 2013	Jun. 30, 2012
Preferred Stock
Schedule of Trading Securities and Other Trading Assets
Less than 12 Months, Fair Value	$ 1,100,000	$ 1,750,000
Less than 12 Months, Unrealized Loss	(10,000)	(16,000)
12 months and Greater, Fair value	1,463,000	1,141,000
12 Months and Greater, Unrealized Loss	(53,000)	(24,000)
Fair value of trading securities in unrealized gain position	18,200,000	16,500,000
Fair Value	2,563,000	2,891,000
Unrealized Loss	$ (63,000)	$ (40,000)