Long-term Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Finance lease obligations	$ 19.6	$ 40.0
Less: Debt issuance costs	(59.8)	(68.9)
Total debt	1,352.8	1,367.0
Less: Current portion of long-term debt	23.4	36.5
Long-term debt	1,329.4	1,330.5
Senior Notes \| 6.000% Senior Secured Notes due March 2022
Debt Instrument [Line Items]
Long-term debt	500.0	500.0
Senior Notes \| 6.375% Senior Secured Notes due March 2025
Debt Instrument [Line Items]
Long-term debt	500.0	500.0
Term Loan \| Senior Secured Term Loan due 2025, net of original issue discount
Debt Instrument [Line Items]
Long-term debt	$ 393.0	$ 395.9

Amount of short-term and long-term debt and lease obligation.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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