Long-term Debt - Derivative (Details) - Cash Flow Hedging [Member]	3 Months Ended
	Sep. 30, 2017 USD ($)
Interest Rate Swap [Member]
Derivative [Line Items]
Notional amount of derivative	$ 300,000,000
Maximum loss on counterparties failure to meet obligations	300,000
Interest Rate Swap Expiring August 2018 [Member]
Derivative [Line Items]
Derivative, amount of hedged items	$ 50,000,000
Fixed interest rate of derivative	1.36%
Variable interest rate of derivative	1.24%
Interest Rate Swap Expiring March 2019 [Member]
Derivative [Line Items]
Derivative, amount of hedged items	$ 100,000,000
Fixed interest rate of derivative	1.53%
Variable interest rate of derivative	1.33%
Interest Rate Swaps Expiring August 2019 [Member]
Derivative [Line Items]
Derivative, amount of hedged items	$ 150,000,000
Fixed interest rate of derivative	1.76%
Variable interest rate of derivative	1.32%
Senior Notes Due 2022 and 2024 [Member] | Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, amount of hedged items	$ 250,000,000
Term Loan Facility [Member] | Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, amount of hedged items	$ 50,000,000