Segment Results (Reconciliation of Total Consolidated Operating Income to Earnings Before Income Taxes) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting [Abstract]
Total consolidated operating income	$ 66.0	$ 69.2	$ 115.6	$ 126.5
Interest expense	9.8	8.9	19.0	17.8
Other non-operating (income), net	(9.1)	(8.3)	(18.1)	(17.2)
Earnings from continuing operations before income taxes	$ 65.3	$ 68.6	$ 114.7	$ 125.9

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Amount of the cost of borrowed funds accounted for as interest expense.

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