Debt, Interest Income, Expense and Other Finance Costs - Schedule of Debt (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Schedule Of Debt Instruments [Line Items]
Total debt	$ 1,151.7	$ 1,186.3
Current maturities of long-term debt and capital leases	23.6	15.4
Long-term debt	1,128.1	1,170.8
Credit Facility
Schedule Of Debt Instruments [Line Items]
Total debt	297.0	325.2
Term Loans
Schedule Of Debt Instruments [Line Items]
Total debt	840.0	840.0
Capital leases
Schedule Of Debt Instruments [Line Items]
Total debt	11.1	12.6
Other
Schedule Of Debt Instruments [Line Items]
Total debt	$ 3.6	$ 8.5