Share-Based Compensation (Share-Based Compensation Expense) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Share based compensation expense	$ 19.6	$ 12.2	$ 42.6	$ 20.8
Tax benefit	(7.5)	(4.7)	(16.3)	(8.0)
After-tax expense	12.1	7.5	26.3	12.8
Stock Options [Member]
Share based compensation expense	5.3	4.2	13.2	(2.5)
Restricted Stock Units (RSUs) [Member]
Share based compensation expense	6.3	4.0	16.4	12.0
Performance Shares [Member]
Share based compensation expense	7.4	4.3	11.3	9.9
Deferred Compensation [Member]
Share based compensation expense	0.5	(0.5)	0.9	(0.1)
Other share based compensation [Member]
Share based compensation expense	$ 0.1	$ 0.2	$ 0.8	$ 1.5