Income Per Common Share Computations (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Earnings Per Share [Abstract]
Net income	$ 7.3	$ 2.8
Participating Securities, Distributed and Undistributed Earnings (Loss), Basic	(0.1)	(0.1)
Income (Loss) from Continuing Operations, Basic	7.2	2.7
Net Income (Loss) Available to Common Stockholders, Diluted	$ 7.3	$ 2.8
Earnings Per Share, Basic and Diluted [Abstract]
Basic	16.3	16.5
Plus dilutive effect of stock options and restricted stock	0.2	0.2
Plus dilutive effect of participating securities	0.3	0.3
Diluted	16.8	17.0
Earnings Per Share, Diluted [Abstract]
Basic	$ 0.44	$ 0.17
Diluted	$ 0.44	$ 0.16