Share-Based Compensation (Details 3) (Nonvested stock awards, USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Nonvested Stock Shares
Nonvested at the beginning of the period (in shares)	4,914,080
Granted (in shares)	1,357,864
Vested (in shares)	(1,651,669)
Forfeited (in shares)	(314,325)
Nonvested at the end of the period (in shares)	4,305,950	4,914,080
Nonvested Stock Shares, Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share)	$ 33.34
Granted (in dollars per share)	$ 46.99
Vested (in dollars per share)	$ 30.35
Forfeited (in dollars per share)	$ 37.39
Nonvested at the end of the period (in dollars per share)	$ 38.50	$ 33.34
Compensation expense	$ 53.2	$ 48.7	$ 45.4
Related income tax benefit recognized	19.6	17.9	16.7
Remaining unamortized expense of nonvested stock expected to be recognized	106.9
Period for expense amortized	2 years 3 months 18 days
Total fair value of shares vested	80.5	53.5	52.5
Shares expected to be repurchased from employees who elect to tender shares to cover minimum tax withholdings	600,000
Legend
Nonvested Stock Shares, Weighted Average Grant Date Fair Value
Compensation expense for discontinued operations		$ 1.2	$ 1.1