Debt (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Short-term borrowings	$ 23.6	$ 45.2
Long-term Debt Types [Abstract]
Total long-term debt	1,495.5	1,191.5
Total Debt	1,519.1	1,236.7
Long-term Debt by Current and Noncurrent [Abstract]
Current liabilities	77.8	97.1
Noncurrent liabilities	1,441.3	1,139.6
Term Loan Facility \| Senior Secured Credit Facility
Long-term Debt Types [Abstract]
Long-term Debt	473.0	491.4
Other Disclosures [Abstract]
Unamortized debt costs	2.0	2.3
Senior unsecured notes \| Six hundred million senior unsecured notes
Long-term Debt Types [Abstract]
Long-term Debt	591.8	591.2
Other Disclosures [Abstract]
Unamortized debt costs	8.2	8.8
Revolving Credit Facility
Long-term Debt Types [Abstract]
Debt	305.7	0.0
Other Non-US Dollar-denominated Facilities
Long-term Debt Types [Abstract]
Debt	8.1	12.0
Capital leases
Long-term Debt Types [Abstract]
Capital Leases	116.9	96.9
Restricted Cash Borrowings
Debt Instrument [Line Items]
Short-term borrowings	11.3	27.0
Other
Debt Instrument [Line Items]
Short-term borrowings	$ 12.3	$ 18.2

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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