Debt Debt - Components of Debt (Details) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Sep. 16, 2014
Debt Instrument [Line Items]
Debt, Long-term and Short-term, Combined Amount	$ 1,980.4	$ 1,983.3
Notes Payable, Related Parties	47.4	48.1
Debt payable within one year	23.1	22.3
Debt payable after one year	$ 1,957.3	$ 1,961.0
Debt, Weighted Average Interest Rate	3.80%	3.90%
Senior Notes, Due 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.125%	5.125%	5.125%
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 2.7	$ 4.2
Debt, Long-term and Short-term, Combined Amount	$ 697.3	$ 695.8
Senior Notes, Due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.625%	5.625%	5.625%
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 2.4	$ 3.0
Debt, Long-term and Short-term, Combined Amount	297.6	297.0
2018 Credit Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	7.2	8.7
Debt, Long-term and Short-term, Combined Amount	930.9	938.9
Other Debt Obligations [Member]
Debt Instrument [Line Items]
Debt, Long-term and Short-term, Combined Amount	$ 7.2	$ 3.5

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

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

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

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Weighted average interest rate of debt outstanding.

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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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