Income Taxes (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	Dec. 31, 2012
Liability for unrecognized tax benefits	$ 51.0		$ 51.0		$ 54.0
Unrecognized tax benefits that would affect income tax expense	42.8		42.8
Interest and penalties share in unrecognized tax benefits			17.2
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	2		2
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Upper Bound	10		10
Effective tax rate on net income from continuing operations	8.70%	18.30%	14.50%
Income tax expense	2.7	6.8	13.6	1.7
Income (loss) from continuing opations before income taxes	$ 30.9	$ 37.1	$ 94.0	$ (0.3)