Derivative Instruments - Fair Value of Derivative Instruments on the Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Jun. 30, 2018
Designated as Cash Flow Hedges | Short-term Investments | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	$ 0	$ 0
Designated as Cash Flow Hedges | Short-Term Derivative Liabilities | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	4,428	3,081
Designated as Cash Flow Hedges | Long-term derivative liabilities | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	493	386
Not Designated as Hedging Instrument | Short-term Investments
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	4	0
Not Designated as Hedging Instrument | Short-Term Derivative Liabilities
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	1,069	219
Not Designated as Hedging Instrument | Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	0	0
Interest Rate Swap [Member] | Designated as Cash Flow Hedges | Short-term Investments | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	144	0
Interest Rate Swap [Member] | Designated as Cash Flow Hedges | Long-term derivative liabilities | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	221	0
Interest Rate Swap [Member] | Not Designated as Hedging Instrument | Short-term Investments
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	0	0
Interest Rate Swap [Member] | Not Designated as Hedging Instrument | Long-term derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	$ 0	$ 0