Segment Information (Reconciliation of Operating Profit from Segment to Consolidated) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting [Abstract]
Operating income (loss)	$ 164.9	$ 122.4	$ (830.0)
Less: interest expense	71.1	77.2	88.4
Less: loss (gain) on debt extinguishment	2.6	(14.1)	0.0
Earnings (loss) before income taxes and equity in loss of unconsolidated entities	$ 91.2	$ 59.3	$ (918.4)