(Loss) Earnings per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Numerator:
Loss from continuing operations	$ (6.2)	$ (14.1)	$ (20.9)	$ (29.6)
Income (loss) from discontinued operations	0.6	(3.3)	(75.8)	(2.2)
Net loss	$ (5.6)	$ (17.4)	$ (96.7)	$ (31.8)
Denominator:
Weighted average number of common shares outstanding during the period - basic (in shares)	37.2	41.1	37.2	41.1
Dilutive effect of stock-based compensation plans (in shares)	0.0	0.0	0.0	0.0
Weighted average number of diluted shares outstanding during the period - diluted (in shares)	37.2	41.1	37.2	41.1
Loss per common share — basic:
Continuing operations (in dollars per share)	$ (0.17)	$ (0.34)	$ (0.56)	$ (0.72)
Discontinued operations (in dollars per share)	0.02	(0.08)	(2.04)	(0.05)
Net loss (in dollars per share)	(0.15)	(0.42)	(2.60)	(0.77)
Loss per common share — diluted:
Continuing operations (in dollars per share)	(0.17)	(0.34)	(0.56)	(0.72)
Discontinued operations (in dollars per share)	0.02	(0.08)	(2.04)	(0.05)
Net loss (dollars per share)	$ (0.15)	$ (0.42)	$ (2.60)	$ (0.77)
Anti-dilutive shares excluded from calculation (in shares)	3.9	3.3	4.5	3.5