Derivative Financial Instruments - Fair Value of Derivative Instruments on the Consolidated Balance Sheets (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014		Jun. 30, 2014
Short-term derivative assets: | Derivative Instruments Designated as Cash Flow Hedges
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 3,692		$ 5,474
Short-term derivative assets: | Derivative Instruments Not Designated as Accounting Hedges
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	6		0
Long-term derivative assets: | Derivative Instruments Designated as Cash Flow Hedges
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	494	[1]	862	[1]
Long-term derivative assets: | Derivative Instruments Not Designated as Accounting Hedges
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	[1]	0	[1]
Short-term derivative liabilities: | Derivative Instruments Designated as Cash Flow Hedges
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	167		252
Short-term derivative liabilities: | Derivative Instruments Not Designated as Accounting Hedges
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0		69
Long-term derivative liabilities: | Derivative Instruments Designated as Cash Flow Hedges
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	20		0
Long-term derivative liabilities: | Derivative Instruments Not Designated as Accounting Hedges
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 0		$ 0

[1] Included in "Other assets" on the consolidated balance sheets.