Employee Share-Based Incentive Compensation Plans (Details 4) (Non-Qualified Options, USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended		1 Months Ended			1 Months Ended
	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	May 31, 2010 Before amendments year	Jan. 31, 2007 Before amendments year	May 26, 2010 Before amendments	May 31, 2010 Amended Grant year	May 26, 2010 Amended Grant
Share-based compensation arrangement by share-based payment award
Stock-based awards, contractual term (in years)					7
Vesting period (in years)					5Y
Initial exercise price (in dollars per share)					$ 650.00
Fair value					$ 27.2	$ 3.5		$ 4.4
Amount amortized into income prior to the modification								18.2
Unamortized amount at modification date						9.0
Annual percentage increase in exercise price (as a percent)					5.00%
Assumptions of stock-based compensation awards
Expected volatility (as a percent)				41.00%	29.70%		34.00%
Risk-free rate (as a percent)				1.57%	1.10%		2.43%
Risk-free rate less the Escalator (as a percent)					4.70%
Forfeiture (as a percent)				0.00%	0.00%		0.00%
Expected dividend yield (as a percent)				0.32%	1.40%		0.32%
Expected life (in years)				3.67	7		6.67
Extension of contractual term (in years)							3
Exercise price (in dollars per share)								$ 742
Number of shares extinguished (in shares)								75,000
Threshold for in-the-money potential							100
Limit on value of in-the-money options over $100 million (as a percent)							50.00%
Expense recognized	$ 10.1	$ 0.1	$ 11.5	$ 8.7
Granted (in shares)					200,000