Incentive Based Compensation Plans (Details 1) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	50,000,000
Share Based Compensation Arrangement By Share Based Payment Award Maximum Award For Options Or Stock Appreciation Rights	2.41
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost	$ 75	$ 70	$ 65
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	27	25	23
Proceeds from Stock Options Exercised	58	41	77
Employee Service Share-based Compensation, Tax Benefit Realized from Exercise of Stock Options	$ 36	$ 24	$ 32
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 33.69
Weighted average exercise price per share	$ 33.54	$ 33.52	$ 32.30
Expected annual dividend yield	2.10%	2.20%	2.10%
Expected life in years	6 years 1 month	5 years 6 months	5 years 4 months
Expected volatility	38.00%	41.00%	40.00%
Risk-free interest rate	2.00%	1.00%	0.00%
End of year weighted average grant date fair value of options	$ 10.25	$ 10.86	$ 10.44
Stock Option [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share Based Payment Award, Award Contractual Period	3 years
Stock Option [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share Based Payment Award, Award Contractual Period	10 years
Stock Appreciation Rights (SARs) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share Based Payment Award, Award Contractual Period	3 years
Stock Appreciation Rights (SARs) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share Based Payment Award, Award Contractual Period	10 years
Restricted Stock [Member] \| Granted Officer [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Restricted Stock [Member] \| Non Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share Based Payment Award, Award Annual Vesting Percentage	33.33%
Restricted Stock [Member] \| Non Officer [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Common Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years

Share-based Compensation Arrangement by Share Based Payment Award, Award Annual Vesting Percentage

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Share-based Compensation Arrangement by Share Based Payment Award, Award Contractual Period

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The maximum number of shares originally approved (usually by shareholders and board of directors), that portion of shares under 2007 plan that may be used for awards other than stock options or stock appreciation rights .

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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-Glossary Financing Activities

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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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