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Debt and Other Financing Arrangements - Debt and Capital Lease Obligations (Details) - USD ($)	Dec. 31, 2015	Jun. 22, 2015	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Long-term debt	$ 996,500,000		$ 644,300,000
Deferred financing costs	(17,600,000)		(15,500,000)
Capital lease obligations	12,200,000		13,400,000
Lease financing arrangements	150,000,000		53,400,000
Total	$ 1,158,700,000		$ 711,100,000
6.375% senior notes due 2022, including bond premium
Debt Instrument [Line Items]
Stated interest rate	6.375%		6.375%
6.375% Senior Notes \| 6.375% senior notes due 2022, including bond premium
Debt Instrument [Line Items]
Long-term debt	$ 477,600,000		$ 374,800,000
Stated interest rate	6.375%
Notes Payable
Debt Instrument [Line Items]
Long-term debt			0
Revolving credit facility
Debt Instrument [Line Items]
Revolving credit facility	$ 235,000,000	$ 650,000,000	135,000,000	$ 0
Term loan
Debt Instrument [Line Items]
Revolving credit facility	$ 300,000,000		$ 150,000,000