Condensed Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement Of Income And Comprehensive Income [Abstract]
Unrealized income on derivatives, net of income taxes	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Employee pension and post retirement benefits, net of income taxes of	$ 3.3	$ 0.0	$ 4.1	$ 0.0