Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reconciliation of information used in computing basic and diluted earnings per share [Abstract]
Net loss	$ (14.9)	$ (14.6)	$ (46.8)	$ (85.9)
Basic loss per common share:
Basic weighted-average shares outstanding	88,429,627	85,047,991	86,239,337	85,038,151
Basic loss per share	$ (0.17)	$ (0.17)	$ (0.54)	$ (1.01)
Diluted earnings (loss) per common share:
Basic weighted-average shares outstanding	88,429,627	85,047,991	86,239,337	85,038,151
Dilutive effect of stock-based awards	0	0	0	0
Diluted weighted-average shares outstanding	88,429,627	85,047,991	86,239,337	85,038,151
Diluted loss per share	$ (0.17)	$ (0.17)	$ (0.54)	$ (1.01)
Weighted average number of anti-dilutive shares excluded from the calculation (in shares)	3,979,018	1,807,022	3,169,495	1,353,762