Basic and Diluted Net Loss Per Share - Schedule of the Computation of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Loss (numerator):
Net loss	$ (92.3)	$ (86.4)
Shares (denominator):
Basic weighted-average common shares outstanding (in shares)	86.6	85.3
Diluted weighted-average common shares outstanding (in shares)	86.6	85.3
Basic and diluted net loss per share:
Basic net loss per share (in USD per share)	$ (1.07)	$ (1.01)
Diluted net loss per share (in USD per share)	$ (1.07)	$ (1.01)