Income Taxes (Income from Continuing Operations Before Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest [Abstract]
Domestic	$ 268.4	$ 383.2	$ 428.7
Foreign	176.8	124.7	39.2
Income from continuing operations before income taxes	$ 445.2	$ 507.9	$ 467.9