Derivative Instruments - Fair Value of Derivative Instruments on the Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Jun. 30, 2017
Designated as Cash Flow Hedges | Short-term Investments | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	$ 233	$ 66
Designated as Cash Flow Hedges | Long-term Derivative Assets | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	99	66
Designated as Cash Flow Hedges | Short-Term Derivative Liabilities | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	1,665	1,733
Designated as Cash Flow Hedges | Other Long Term Liabilities | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	0	446
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	0	0
Not Designated as Hedging Instrument | Short-term Investments
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	40	0
Not Designated as Hedging Instrument | Long-term Derivative Assets
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	0	0
Not Designated as Hedging Instrument | Short-Term Derivative Liabilities
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	$ 258	$ 190