Information Relating to the Consolidated Statement of Cash Flows (Details Textual) (USD $) Share data in Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Supplemental Cash Flow Elements [Abstract]
Reduction for income tax benefits associated with stock options exercised	$ 28,000,000	$ 26,000,000
Net purchases of treasury shares	1,300,000,000	1,300,000,000
Stock repurchased during period (in shares)	10.8	11.6
Stock repurchased during period	$ 1,250,000,000	$ 1,250,000,000

The cash outflow to reacquire common stock during the period.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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