Share-Based Compensation Plans (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based employee compensation expense	$ 80.8	$ 74.5	$ 69.3
Unamortized share-based employee compensation, amortization period	5 years
Unamortized share-based employee compensation	302.5
Option Activity [Roll Forward]
Balance January 1	18,301,409	24,513,590	40,832,715
Options granted under 2007 Plan	60,000	90,000	335,000
Options exercised	(12,673,529)	(6,034,181)	(14,125,525)
Options forfeited	(97,000)	(268,000)	(2,528,600)
Balance December 31	5,590,880	18,301,409	24,513,590
Exercisable December 31	5,333,880	9,672,909	7,885,090
Balance January 1, Weighted Average Exercise Price	$ 26.22	$ 26.64	$ 29.37
Options granted under 2007 Plan, Weighted Average Exercise Price	$ 49.65	$ 45.05	$ 38.86
Options exercised, Weighted Average Exercise Price	$ 26.47	$ 28.17	$ 33.03
Options forfeited, Weighted Average Exercise Price	$ 35.98	$ 27.15	$ 36.58
Balance December 31, Weighted Average Exercise Price	$ 25.72	$ 26.22	$ 26.64
Exercisable December 31, Weighted Average Exercise Price	$ 24.89	$ 27.85	$ 31.80
Options Outstanding and Exercisable [Abstract]
Options Outstanding, Shares	5,590,880
Options Exercisable, Shares	5,333,880
Black-Scholes Assumptions and Weighted Average Fair Value Per Share for Options Granted [Abstract]
Expected option lives	5 years	5 years	5 years
Risk free interest rate	0.80%
Risk free interest rate, minimum		0.90%	1.80%
Risk free interest rate, maximum		1.80%	2.60%
Expected volatility	29.50%
Expected volatility, minimum		27.20%	24.70%
Expected volatility, maximum		29.20%	27.00%
Dividend yield	.0313	2.3% - 2.8%	1.9% - 2.4%
Weighted average fair value per option granted	$ 10,420,000	$ 9,570,000	$ 8,250,000
Exersices Price Range - $23.40 to $29.99 [Member]
Options Outstanding and Exercisable [Abstract]
Range of Exercise Prices, lower range limit	$ 23.40
Range of Exercise Prices, upper range limit	$ 29.99
Options Outstanding, Shares	4,992,880
Options Outstanding, Weighted Average Remaining Contractual Life	6 years 2 months
Options Outstanding, Weighted Average Exercise Price	$ 23.61
Options Exercisable, Shares	4,992,880
Options Exercisable, Weighted Average Exercise Price	$ 23.61
Exersices Price Range - $30.00 to $44.99 [Member]
Options Outstanding and Exercisable [Abstract]
Range of Exercise Prices, lower range limit	$ 30.00
Range of Exercise Prices, upper range limit	$ 44.99
Options Outstanding, Shares	362,000
Options Outstanding, Weighted Average Remaining Contractual Life	7 years 6 months
Options Outstanding, Weighted Average Exercise Price	$ 38.57
Options Exercisable, Shares	206,000
Options Exercisable, Weighted Average Exercise Price	$ 38.13
Exersices Price Range - $45.00 to $52.83 [Member]
Options Outstanding and Exercisable [Abstract]
Range of Exercise Prices, lower range limit	$ 45.00
Range of Exercise Prices, upper range limit	$ 52.83
Options Outstanding, Shares	236,000
Options Outstanding, Weighted Average Remaining Contractual Life	5 years 4 months
Options Outstanding, Weighted Average Exercise Price	$ 50.64
Options Exercisable, Shares	135,000
Options Exercisable, Weighted Average Exercise Price	$ 52.11
Stock Options [Member]
Share-based employee compensation, terms of award	The exercise price of stock option awards may not be less than 100% of the market price of our common stock on the grant date and the option term cannot exceed ten years from the grant date.
Share-based employee compensation, vesting rights	Typically, stock option awards vest 30% per year for the first two years and are fully vested three years from the grant date.
Restricted Stock [Member]
Share-based employee compensation, vesting rights	Restricted shares typically vest 20% per year, provided the employee remains employed by us and are fully vested five years from the grant date.
Restricted Stock and PRSU Activity [Roll Forward]
Balance January 1	6,038,978	3,026,086	3,471,929
Shares granted	2,515,127	4,274,807	868,273
Shares vested	(981,737)	(1,096,441)	(1,089,136)
Shares forfeited	(330,878)	(165,474)	(224,980)
Balance December 31	7,241,490	6,038,978	3,026,086
Restricted Stock and PRSU Activity, Weighted Average Grant Date Fair Value [Roll Forward]
Balance January 1, Weighted Average Grant Date Fair Value	$ 43.32	$ 41.79
Granted, Weighted Average Grant Date Fair Value	$ 49.55	$ 44.51	$ 36.63
Balance December 31, Weighted Average Grant Date Fair Value	$ 45.34	$ 43.32	$ 41.79
Performance Restricted Stock Units (PRSUs) [Member]
Share-based employee compensation, vesting rights	Each PRSU represents the right to receive one share of common stock on vesting. The ultimate number of PRSUs received by the employee depends on the Company's average return on equity over a three year period compared to the average return on equity of a peer group of five principal competitors over the same period. The 2011 PRSUs vest over five years and the 2012 PRSUs vest over three years.
Restricted Stock and PRSU Activity [Roll Forward]
Balance January 1	413,909	0
Shares granted	166,426	413,909
Shares vested	(41,387)	0
Shares forfeited	0	0
Balance December 31	538,948	413,909
Restricted Stock and PRSU Activity, Weighted Average Grant Date Fair Value [Roll Forward]
Balance January 1, Weighted Average Grant Date Fair Value	$ 48.56
Granted, Weighted Average Grant Date Fair Value	$ 49.13	$ 48.56
Distributed, Weighted Average Grant Date Fair Value	$ 48.56	$ 0.00
Forfeited, Weighted Average Grant Date Fair Value	$ 0.00	$ 0.00
Balance December 31, Weighted Average Grant Date Fair Value	$ 48.74	$ 48.56
Employee Stock Purchase Plan (ESPP) [Member]
Shares available for grant	9,366,378
Employee Stock Purchase Plan (ESPP) [Abstract]
Discount from market price	95.00%
Maximium percentage of eligible compensation allowable for purchase	10.00%
Shares issued in period	189,307	161,929	267,931
Proceeds from issuance of shares	$ 8.6	$ 7.0	$ 9.7
2007 Incentive Award Plan [Member]
Maximum of shares available for issuance	17,000,000
Stock awards other than options, conversion ratio	2.5
Shares available for grant	384,826
Stock awards other than options, shares availiable for grant	153,930