Net Income Attributable to Company Per Share - Computation of Weighted Average Basic and Diluted Shares Outstanding (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Numerator:
Net income attributable to Company	$ 636	$ 612	$ 1,669	$ 1,823
Denominator:
Basic-weighted average common shares outstanding	426	425	426	425
Dilutive effect of employee stock options and other unvested stock awards	2	2	2	1
Diluted outstanding shares	428	427	428	426
Net income attributable to Company per share:
Basic	$ 1.49	$ 1.44	$ 3.92	$ 4.29
Diluted	$ 1.49	$ 1.43	$ 3.90	$ 4.28
Cash dividends per share	$ 0.26	$ 0.12	$ 0.65	$ 0.36

Aggregate dividends paid during the period for each share of common stock outstanding.

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