Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net Income (loss)	$ (19.5)	$ 2.1	$ (54.0)	$ (12.1)
Average shares of stock outstanding - basic and diluted	142,300,000	140,800,000	142,100,000	140,800,000
Incremental Common Shares Attributable to Dilutive Effect of Call Options and Warrants		1,300,000
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements		1,900,000
Weighted Average Number of Shares Outstanding, Diluted	142,300,000	144,000,000	142,100,000	140,800,000
Net income (loss) per share - basic	$ (0.14)	$ 0.01	$ (0.38)	$ (0.09)
Diluted earnings per share:
Antidilutive securities excluded from computation of earnings per share	5,100,000	4,100,000	5,100,000	3,500,000
Warrants outstanding	573,521		573,521