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Commitments And Contingencies (Environmental Matters) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended |  | 9 Months Ended | 3 Months Ended | 1 Months Ended | 3 Months Ended | 12 Months Ended |  | 12 Months Ended
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Sep. 30, 2011 | Sep. 30, 2011 | Dec. 31, 2010 | Sep. 30, 2011 Recurring Costs of Managing Hazardous Substances and Environmental Programs [Member] | Sep. 30, 2011 Various Sites [Member] | Nov. 30, 2008 Grasse River [Member] | Jun. 30, 2003 Grasse River [Member] | Sep. 30, 2011 Grasse River [Member] | Dec. 31, 2010 Grasse River [Member] | Mar. 24, 2010 Grasse River [Member] | Dec. 31, 2005 East St. Louis Site [Member] | Dec. 31, 2009 Fusina Site [Member] | Dec. 31, 2009 Portovesme Site [Member]
Number of cleanup locations |  | more than 100 |  |  |  |  |  |  |  |  |  |  |
Remediation reserve balance | $ 327 | $ 327 | $ 333 |  |  |  |  |  |  |  |  |  |
Remediation reserve balance, classified as a current liability | 34 | 34 | 31 |  |  |  |  |  |  |  |  |  |
Remediation reserve increase |  | 6 |  |  | 2 | 40 |  |  | 2 |  | 15 | 12 | 3
Remediation reserve adjustment |  |  |  |  |  |  |  |  |  | 17 |  |  |
Payments related to remediation expenses applied against the reserve | 5 | 13 |  |  |  |  |  |  |  |  |  |  |
Percentage of cost of goods sold |  |  |  | 2.00% |  |  |  |  |  |  |  |  |
Recommended capping remedy, minimum |  |  |  |  |  |  |  | 20 |  |  |  |  |
Recommended capping remedy, maximum |  |  |  |  |  |  |  | 100 |  |  |  |  |
Translation adjustment functional to reporting currency | $ (2) | $ 1 |  |  |  |  |  |  |  |  |  |  |
Frequency of sediment erosion from winter river ice formation and breakup, in years |  |  |  |  |  |  | 10 |  |  |  |  |  |

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