Earnings Per Share - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Net loss attributable to shareholders	$ (48.7)	$ (78.6)	$ (172.9)	$ (245.6)
Weighted average shares outstanding for basic and diluted loss per share (in shares)	184.0	144.1	158.5	143.6
Basic and diluted loss per common share attributable to shareholders (in dollars per share)	$ (0.26)	$ (0.55)	$ (1.09)	$ (1.71)