Long-Term Debt - Summary of Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Finance/capital lease obligations, interest rates between 3.70% and 7.73%, maturing through 2024	$ 52.6	$ 52.6
Finance/capital lease obligations, interest rates between 3.70% and 7.73%, maturing through 2024			$ 69.2
Other debt	8.1		9.5
Total debt	1,888.2		1,928.2
Less: Original issue discount	(20.0)		(25.2)
Less: Current portion	(76.1)		(85.9)
Long-term debt, less original issue discount and current maturities	1,792.1		1,817.1
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt	30.0		37.0
Term Loan B
Debt Instrument [Line Items]
Long-term debt	1,372.5		1,387.5
Senior notes
Debt Instrument [Line Items]
Long-term debt	$ 425.0		$ 425.0

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

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