Long-term Debt - Schedule of Debt (Details) - Successor - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Capital lease and other obligations	$ 67.8	$ 76.0
Less: Debt issuance costs	(56.9)	(59.4)
Total debt	1,455.2	1,460.8
Less: Current portion of long-term debt	87.1	42.1
Long-term debt	1,368.1	1,418.7
Senior Notes \| 6.000% Senior Secured Notes due March 2022
Debt Instrument [Line Items]
Long-term debt	$ 500.0	$ 500.0
Stated interest rate	6.00%	6.00%
Senior Notes \| 6.000% Senior Secured Notes due March 2022
Debt Instrument [Line Items]
Long-term debt	$ 500.0	$ 500.0
Stated interest rate	6.375%	6.375%
Term Loan \| Senior Secured Term Loan due 2025
Debt Instrument [Line Items]
Long-term debt	$ 444.3	$ 444.2

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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