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Income Taxes (Schedule Of Changes In Valuation Allowance) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2011 | Dec. 31, 2010
Income Taxes [Abstract] |  |  |  |
Balance at beginning of year | $ 1,268 |  | $ 1,345 |
Increase to allowance | 157 |  | 25 |
Release of allowance | (25) | [1] | (90) | [1]
Acquisitions/Divestitures |  |  | (3) |
Foreign currency translation | (2) |  | (9) |
Balance at end of year | 1,398 |  | 1,268 |
Reversal of valuation allowance |  |  | $ 57 |
[1] | * In 2010, this amount includes $57 for the reversal of a valuation allowance related to previously restricted net operating losses of a foreign subsidiary now available.

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- Definition The amount of the valuation allowance recorded as of the balance sheet date pertaining to the specified deferred tax asset for which an assessment was made that it is more likely than not that all or a portion of such deferred tax asset will not be realized through related deductions on future tax returns. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 43 -Subparagraph c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Valuation Allowance -URI http://asc.fasb.org/extlink&oid=6528051 + Details
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