Income Taxes - Schedule of Income from Operations Before Provision for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Domestic	$ 102.2	$ 146.4	$ 114.1
Foreign	0.3	1.0	1.3
Income from continuing operations before provision for income taxes	$ 102.5	$ 147.4	$ 115.4