Earnings Per Share (Details) (USD $) In Millions, except Per Share data	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Basic EPS
Income from continuing operations	$ 1,775	$ 1,225	$ 4,999	$ 3,435
Less: Net income attributable to noncontrolling interest		(22)		(58)
Income from continuing operations attributable to common stock	1,775	1,203	4,999	3,377
Discontinued operations, net	(4)	(12)	138	(59)
Net income attributable to common stock	1,771	1,191	5,137	3,318
Less: Net income allocated to participating securities	(4)	(2)	(8)	(4)
Net income attributable to common stock, net of participating securities	1,767	1,189	5,129	3,314
Weighted average number of basic shares (in shares)	812.5	812.7	812.6	812.4
Basic EPS (in dollars per share)	$ 2.17	$ 1.46	$ 6.31	$ 4.08
Diluted EPS
Net income attributable to common stock, net of participating securities	$ 1,767	$ 1,189	$ 5,129	$ 3,314
Weighted average number of basic shares (in shares)	812.5	812.7	812.6	812.4
Dilutive effect of potentially dilutive securities (in shares)	0.7	1.2	0.7	1.4
Total diluted weighted average common shares (in shares)	813.2	813.9	813.3	813.8
Diluted EPS (in dollars per share)	$ 2.17	$ 1.46	$ 6.31	$ 4.07

This element represents the net income (loss) attributable to participating securities, which are nonvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid). The shares are considered participating securities prior to vesting, and therefore have been included in the earnings allocations in computing basic and diluted EPS under the two-class method.

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- Definition

The amount of net income or loss for the period per each share of common stock outstanding during the reporting period.

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-Name Regulation S-X (SX)

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- Definition

The amount of net income or loss for the period per each share of common stock and dilutive common stock equivalents outstanding during the reporting period.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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- Definition

This element represents the income or loss from continuing operations attributable to the reporting entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items and cumulative effects of changes in accounting principles, but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests, if any.

+ References

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 29

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-Number 51

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-Paragraph 38

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.

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This element represents the overall income (loss) from a disposal group that is classified as a component of the entity, net of income tax, reported as a separate component of income before extraordinary items and the cumulative effect of accounting changes before deduction or consideration of the amount which may be allocable to noncontrolling interests, if any. Includes the following (net of tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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-Number 144

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- Definition

Aggregate awards of share options and nonvested shares to be issued to an employee under a share-based compensation arrangement are considered options for purposes of computing diluted earnings per share. Such share-based awards shall be considered to be outstanding as of the grant date for purposes of computing diluted earnings per share even though their exercise may be contingent upon vesting. Those share-based awards are included in the diluted Earnings Per Share (EPS) computation even if the employee may not receive (or be able to sell) the stock until some future date. Accordingly, all shares to be issued shall be included in computing diluted EPS if the effect is dilutive. The dilutive effect of share-based compensation arrangements shall be computed using the treasury stock method. If the equity share options or other equity instruments are outstanding for only part of a period, the shares issuable shall be weighted to reflect the portion of the period during which the equity instruments were outstanding.

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-Publisher FASB

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- Definition

The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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The portion of net income (loss) attributable to the noncontrolling interest (if any) deducted in order to derive the portion attributable to the parent.

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-Publisher AICPA

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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- Definition

The average number of shares issued and outstanding that are used in calculating diluted EPS, determined based on the timing of issuance of shares in the period.

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Number of [basic] shares, after adjustment for contingently issuable shares and other shares not deemed outstanding, determined by relating the portion of time within a reporting period that common shares have been outstanding to the total time in that period.

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