Income Taxes (Details) (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Jun. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Income Taxes (Amounts in paragraphs)
Effective tax rate on income from continuing operations	31.10%	33.30%		33.20%	18.30%
Recognition of net tax benefits, as a result of the settlement	$ 14		$ 298
Recognition of net tax benefits, as a result of the settlement, in cash			66
Reduction in liability for uncertain tax provisions			$ 311

Income Taxes.

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Reflects the cash effects of adjustments of previously recorded tax expense, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, IRS tax settlement and unusual repatriation of foreign earnings.

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A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 47

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The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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-Paragraph 15

-Subparagraph (c)

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Reflects the effects of adjustments of previously recorded tax expense, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, IRS tax settlement and unusual repatriation of foreign earnings.

+ References

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-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 48

-Paragraph 10

-Subparagraph b

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