Income from Continuing Operations Per Unrestricted Share (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Schedule of Basic and Diluted Earnings Per Share [Line Items]
Income from Continuing Operations	$ 4.8	$ 68.6	$ 49.3	$ 159.7
Dilutive Effect on Income of Equity-based Compensation Equivalent Shares	0	0	0	0
Diluted Income from Continuning Operations Attributed to Unrestricted Shares	4.8	68.3	49.1	158.9
Weighted-Average Unrestricted Shares Outstanding	52,605,300	56,365,800	54,245,700	57,374,400
Equity-based Compensation Equivalent Shares	94,600	135,700	110,500	118,800
Weighted-Average Unrestricted Shares and Equivalent Shares Outstanding Assuming Dilution	52,699,900	56,501,500	54,356,200	57,493,200
Basic Income from Continuing Operations Per Unrestricted Share (in dollars per share)	$ 0.09	$ 1.21	$ 0.90	$ 2.77
Diluted Income from Continuing Operations Per Untrestriced Share (in dollars per share)	$ 0.09	$ 1.21	$ 0.90	$ 2.76
Unrestricted Shares [Member]
Schedule of Basic and Diluted Earnings Per Share [Line Items]
Income from Continuing Operations	4.8	68.3	49.1	158.9
Participating Awards [Member]
Schedule of Basic and Diluted Earnings Per Share [Line Items]
Income from Continuing Operations	$ 0	$ 0.3	$ 0.2	$ 0.8