Income Taxes (Schedule of Income Tax Expense and Effective Tax Rate) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income before income taxes and equity in net income (loss) of unconsolidated entities	$ 35.7	$ 63.5	$ 53.1	$ 46.2	$ 48.4	$ 72.7	$ 55.0	$ 56.8	$ 198.5	$ 232.9	$ 181.1
Equity in net income (loss) of unconsolidated entities	1.0	(1.1)	0.7	(1.5)	(0.5)	0.3	(0.4)	(1.5)	(0.9)	(2.1)	(1.3)
Income loss from continuing operations before income taxes domestic and foreign									197.6	230.8	179.8
Income tax expense	$ 9.1	$ 13.3	$ 11.7	$ 11.5	$ 5.5	$ 16.1	$ 12.8	$ 13.4	$ 45.6	$ 47.8	$ 42.9
Effective income tax rate									23.10%	20.70%	23.90%