Acquisition and Discontinued Operations (Summary of Results of Discontinued Operations) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income tax (benefit)	$ (5.9)	$ (14.7)	$ (5.4)	$ (16.6)
Net (loss) gain on disposal of discontinued business	5.9	14.7	5.3	16.7
DLW and AFI [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
(Loss) gain on disposal of discontinued business before income tax			(0.1)	0.1
Income tax (benefit)	(5.9)	(14.7)	(5.4)	(16.6)
Net (loss) gain on disposal of discontinued business	$ 5.9	$ 14.7	$ 5.3	$ 16.7