Debt - Components of Debt (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Debt payable—unconsolidated affiliate	$ 47.0	$ 47.4
Total debt	1,978.3	1,980.4
Debt payable within one year	23.5	23.1
Debt payable after one year	$ 1,954.8	$ 1,957.3
Weighted average interest rates on total debt	3.70%	3.80%
2025 Term Loan
Debt Instrument [Line Items]
Total debt	$ 928.8	$ 930.9
Unamortized discount and debt issuance costs	6.9	7.2
5.125% Senior Notes, Due 2021
Debt Instrument [Line Items]
Total debt	697.7	697.3
Debt Issuance Costs, Net	2.3	2.7
5.625% Senior Notes, Due 2024
Debt Instrument [Line Items]
Total debt	297.7	297.6
Debt Issuance Costs, Net	2.3	2.4
Other borrowings
Debt Instrument [Line Items]
Total debt	$ 7.1	$ 7.2

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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-Name Accounting Standards Codification
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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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- Definition

Weighted average interest rate of debt outstanding.

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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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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The amount for notes payable (written promise to pay), due to related parties.

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