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) |