Supplementary Data Other (Expense) Income, Net (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Other Income and Expenses [Abstract]
Gains (losses) on sales of businesses and investments	$ 1.0	$ (16.3)
Other expense, net	(0.2)	(2.9)
Total other income (expense), net	$ 0.8	$ (19.2)