Debt, Interest Income, Expense and Other Finance Costs - Schedule of Debt (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Finance Leases	$ 16.7
Finance Leases		$ 13.8
Total debt	695.5	701.0
Current maturities of long-term debt and finance leases	45.8	41.1
Long-term debt	649.7	659.9
Credit Facility
Debt Instrument [Line Items]
Long-term debt	170.0	170.0
Term Loans
Debt Instrument [Line Items]
Long-term debt	506.4	514.8
Other
Debt Instrument [Line Items]
Long-term debt	$ 2.4	$ 2.3

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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