Segment Results (Reconciliation of Total Consolidated Operating Income to Earnings Before Income Taxes) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting [Abstract]
Total consolidated operating income	$ 81.3	$ 73.9	$ 196.9	$ 200.4
Interest expense	9.9	8.8	28.9	26.6
Other non-operating (income) expense, net	(9.2)	12.3	(27.3)	(4.9)
Earnings from continuing operations before income taxes	$ 80.6	$ 52.8	$ 195.3	$ 178.7