Derivative Financial Instruments - Schedule of Offsetting Derivative Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Jun. 30, 2013
Counterparty A:
Derivative [Line Items]
Derivative Asset, Gross Amount Reported on Balance Sheet	$ 19,825	$ 4
Derivative Asset - Netting Adjustment	(57)	(4)
Cash Collateral Posted	0	0
Derivative Assets - Net Exposure	19,768	0
Derivative Liability - Gross Amount Reported on Balance Sheet	57	11,025
Derivative Liability - Netting Adjustment	(57)	(4)
Derivative Liability - Cash Collateral Received	0	8,084
Derivative Liabilities - Net Exposure	0	2,937
Counterparty B:
Derivative [Line Items]
Derivative Asset, Gross Amount Reported on Balance Sheet	0	0
Derivative Asset - Netting Adjustment	0	0
Cash Collateral Posted	0	0
Derivative Assets - Net Exposure	0	0
Derivative Liability - Gross Amount Reported on Balance Sheet	0	25
Derivative Liability - Netting Adjustment	0	0
Derivative Liability - Cash Collateral Received	0	0
Derivative Liabilities - Net Exposure	$ 0	$ 25