Impairments, Restructuring Charges, and Other Items (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Summary of impairment, restructuring, and other charges
Severance, restructuring costs, and special termination benefits	$ 6.6	$ 0.6	$ 9.4	$ 2.6
Business process re-engineering	0.6	0	2.7	0
Reserve for former corporate headquarters	0	0	0.5	0
Environmental reserve for sold building	0.2	0	0.2	0
Curtailment and settlement gain on postretirement benefits	0	0	0	(45.0)
Total impairments, restructuring charges, and other items	$ 7.4	$ 0.6	$ 12.8	$ (42.4)