Segment Results (Reconciliation of Total Consolidated Operating Income to Earnings Before Income Taxes) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Segment Reporting [Abstract]
Total consolidated operating income	$ 63.0	$ 21.6
Interest expense	9.2	21.9
Other non-operating expense	1.8
Other non-operating (income)	(3.4)	(5.2)
Earnings from continuing operations before income taxes	$ 55.4	$ 4.9