Share-Based Compensation (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2011 years	Dec. 31, 2010	Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized to issued under ESPP	3,000,000
Shares authorized but not issued under the ESPP	189,297
Share-based compensation expense for stock options and shares issued under ESPP	$ 27,000,000	$ 28,000,000	$ 27,000,000
Share-based compensation expense for stock options and shares issued under the ESPP, net of tax	15,000,000	21,000,000	11,000,000
Restricted stock expense	112,000,000	111,000,000	94,000,000
Restricted stock expense net of tax	73,000,000	79,000,000	75,000,000
Unrecognized compensation expense related to the unvested portion of the employee share-based awards	120,000,000
Weighted-average period in years over which the unrecognized compensation expense related to the unvested portion of the Company's employee share-based award will be recognized	1
Non-qualified stock options price per share percent of the fair value	100.00%
Weighted-average remaining contractual term in years for stock options outstanding	6.1
Weighted-average remaining contractual term in years for stock options exercisable	4.7
Share-based compensation arrangement by share-based payment award, award vesting period, years	3
Stock option term in years	10
Intrinsic value for stock options outstanding	215,000,000
Intrinsic value for stock options exercisable	157,000,000
Weighted-average fair value for stock options granted	$ 14.67	$ 12.09	$ 12.95
Total intrinsic value for stock options exercised	63,000,000	22,000,000	12,000,000
Cash received from the exercise of stock options	121,000,000
Restricted stock award and units vesting period in years	1
Weighted average grant date fair value of awards except for options granted to employees and officers of the company	$ 62.85	$ 50.36	$ 38.75
Amount of common shares delivered for each restricted stock unit	1
Restricted stock units awarded to employees, and officers of the company	261,214	326,091	333,104
Restricted stock units awarded to non-management directors	32,660	36,248
ESPP - Percentage of purchase price fair value paid by employees	85.00%
ESPP - Contribution limitation	25,000
ESPP - Salary percentage limitation	10.00%
ESPP - Employee contributions	$ 11,800,000
ESPP - Shares purchased	205,812
ESPP - Number of subscription periods per year	2
Unvested restricted stock units	656,837
Deferred restricted stock units	226,503
2004 LTIP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares authorized to issued		30,600,000
Shares remain available for future issuance	9,411,758
Restricted stock award and units vesting period in years	4