Incentive Based Compensation Plans (Details 2) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Number of Shares
Beginning year stock option awards	19,536,965
Granted stock option awards	2,051,386
Exercised stock option awards	(2,718,639)
Canceled stock option awards	(764,825)
End of year stock option awards	18,104,887	19,536,965
Weighted Average Exercise price
Beginning year weighted average exercise price	$ 26.19
Granted weighted average exercise price	$ 33.54	$ 33.52	$ 32.30
Exercises weighted average exercise price	$ 22.36
Canceled weighted average exercise price	$ 34.02
End of year weighted average exercise price	$ 27.27	$ 26.19
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value	$ 35	$ 40	$ 59

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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-Name Accounting Standards Codification

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Net number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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