Net Income Attributable to Company Per Share (Details) (USD $) In Millions, except Per Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Numerator:
Net income attributable to Company	$ 481	$ 401	$ 888	$ 823
Denominator:
Basic-weighted average common shares outstanding	422	417	421	417
Dilutive effect of employee stock options and other unvested stock awards	3	2	3	2
Diluted outstanding shares	425	419	424	419
Net income attributable to Company per share:
Basic	$ 1.14	$ 0.96	$ 2.11	$ 1.97
Diluted	$ 1.13	$ 0.96	$ 2.10	$ 1.96
Cash dividends per share	$ 0.11	$ 0.10	$ 0.22	$ 0.20
Net Income Attributable to Company Per Share (Textuals) [Abstract]
Anti-dilutive stock options outstanding	2	6	3	5

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