Income Taxes (Narrative) (Details) (USD $) In Millions	1 Months Ended	3 Months Ended
Dec. 31, 2010	Mar. 31, 2010	Sep. 30, 2011	Dec. 31, 2009
Income Tax Disclosure [Abstract]
Reduction of deferred tax asset due to Medicare prescription drug benefit subsidy		$ 7
Increase (decrease) in accrued taxes payable due to application of MTR	(27)	(43)
Accrued income taxes, Mexican Tax Reform Bill			$ 4	$ 73

The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to the subsidy for Medicare prescription drug benefits received tax-free.

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

-Publisher FASB

-Name FASB Staff Position (FSP)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Section 50

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