Income Taxes (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Income Taxes
Estimated annual effective tax rate (as a percent)	29.00%	28.00%	25.00%
Tax benefit, repatriation of non-U.S. earnings due to available foreign tax credits in excess of the U.S. tax liability on the dividend	$ 113
Increase in prior year unrecognized tax benefits	41
Tax law change related to Medicare subsidies		90
Tax benefits related to prior year tax returns		34
Reversal of valuation allowance for deferred tax assets		$ 26

This element represents deferred tax charge included in the provision for income taxes in the period, expressed as a portion of the effective rate, due to the enactment of U.S. Healthcare legislation effectively making government subsidies received for prescription drug coverage taxable.

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- Definition

The portion of the difference between total income tax expense (benefit) as reported in the Income Statement for the current period and the expected income tax expense (benefit) computed, which is attributable to reversal of valuation allowance for deferred tax assets.

+ Details

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- Definition

Tax benefit on the repatriation of non-U.S. earnings due to available foreign tax credits in excess of the U.S. tax liability on the dividend.

+ Details

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- Definition

The portion of the difference between total income tax expense (benefit) as reported in the Income Statement for the current period and the expected income tax expense (benefit) computed attributable to tax benefits related to prior year tax returns.

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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(2))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 2

-Article 4

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319

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- Definition

The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

+ References

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

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 48

-Paragraph 21

-Subparagraph a(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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