Income Taxes (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reconciliation of the beginning and ending of unrecognized tax benefits
Balance at January 1	$ 125.9	$ 64.4	$ 121.5
Additions based on tax positions related to the current period	11.9	13.0	2.2
Additions for tax positions of prior periods	71.7	69.8	48.6
Reductions for tax positions of prior periods	(92.1)	(18.6)	(75.8)
Statute expirations	(1.9)	(1.9)	(2.3)
Settlements	(5.4)	(0.8)	(29.8)
Balance at December 31	$ 110.1	$ 125.9	$ 64.4