Long-term Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total finance lease liabilities	$ 27.3	$ 15.2
Less: Debt issuance costs	(42.7)	(55.5)
Long-term Debt and Lease Obligation, Including Current Maturities	1,547.8	1,310.8
Less: Current portion of long-term debt	44.9	18.3
Long-term debt	1,502.9	1,292.5
Senior Notes \| 6.000% Senior Secured Notes due March 2022
Debt Instrument [Line Items]
Long-term debt	$ 459.0	459.0
Stated interest rate	6.00%
Senior Notes \| 6.375% Senior Secured Notes due March 2025
Debt Instrument [Line Items]
Long-term debt	$ 500.0	500.0
Stated interest rate	6.375%
Term Loan \| Senior Secured Term Loan due 2025, net of original issue discount
Debt Instrument [Line Items]
Long-term debt	$ 388.2	392.1
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt	$ 216.0	$ 0.0

Contractual interest rate for funds borrowed, under the debt agreement.

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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, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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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