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Contingencies And Commitments (Environmental Matters) (Narrative) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended | 1 Months Ended | 12 Months Ended |  | 1 Months Ended | 12 Months Ended |  | 12 Months Ended |  | 12 Months Ended
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Dec. 31, 2011 | Dec. 31, 2010 | Jun. 30, 2003 Massena West, NY [Member] | Dec. 31, 2010 Massena West, NY [Member] | Dec. 31, 2011 U.S. Smelters [Member] | Dec. 31, 2010 U.S. Smelters [Member] | Nov. 30, 2008 Grasse River [Member] | Dec. 31, 2011 Grasse River [Member] | Dec. 31, 2010 Grasse River [Member] | Mar. 24, 2010 Grasse River [Member] | Dec. 31, 2005 East St. Louis, IL [Member] | Dec. 31, 2008 Vancouver Smelter Site [Member] | Dec. 31, 2009 Columbia River [Member] | Dec. 31, 2009 Fusina Site [Member] | Dec. 31, 2009 Portovesme Site [Member] | Dec. 31, 2010 Russia Facility [Member] | Dec. 31, 2011 Other Sites [Member] | Dec. 31, 2010 Other Sites [Member] | Dec. 31, 2011 Aerospace Fasteners Business [Member] | Dec. 31, 2011 Recurring Costs Of Managing Hazardous Substances And Environmental Programs [Member]
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of cleanup locations | more than 100 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Remediation reserve balance | $ 347 | $ 333 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Remediation reserve balance, classified as a current liability | 58 | 31 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Remediation reserve increase |  |  |  | 46 | 31 |  | 40 | 1 | 2 |  | 15 | 16 | 2 | 12 | 3 |  | 13 | 11 |  |
Remediation reserve adjustment |  |  |  | 19 | 18 | 14 |  |  |  | 17 |  |  |  |  |  | 9 |  |  |  |
Charges related to settlement offer made for outstanding claims |  |  |  | 11 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Period of time between potential phenomenon occurrences, years |  |  | 10 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments related to remediation expenses applied against the reserve | 19 | 17 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of cost of goods sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.00%
Recommended capping remedy min | 20 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recommended capping remedy max | 100 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Increase (decrease) in reserves due to effects of foreign currency translation | $ (1) | $ (3) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3 |

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