Net Income Attributable to Company Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Numerator:
Net income attributable to Company	$ 606	$ 407
Denominator:
Basic-weighted average common shares outstanding	423	420
Dilutive effect of employee stock options and other unvested stock awards	3	3
Diluted outstanding shares	426	423
Net income attributable to Company per share:
Basic	$ 1.43	$ 0.97
Diluted	$ 1.42	$ 0.96
Cash dividends per share	$ 0.12	$ 0.11
Net Income Attributable to Company Per Share (Textual) [Abstract]
Anti-dilutive stock options outstanding	6	3

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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