Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Effective income tax rate on continuing operations (as a percent)	26.10%	31.30%
Anticipated effective tax rate for beginning of year to date (as a percent)	24.70%
Discrete income tax expense (benefit)	$ 1.1	$ (1.5)