Subsequent Event (Details) - USD ($)	Oct. 28, 2015	Sep. 30, 2015
Line of Credit [Member]
Subsequent Event [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 215,000,000
Line of Credit [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 300,000,000
Debt Instrument, Fee Amount	$ 1,900,000
Letter of Credit [Member]
Subsequent Event [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		100,000,000
2019 Notes [Member] | Senior Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount		200,000,000
Debt, Current		$ 40,000,000.0