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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2008
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Domestic [Member]
12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : International [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled funds [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Post retirement Benefit Plans Defined Benefit [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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USD ($)
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USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Domestic [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Private equity [Member]
12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Private equity [Member]
12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : U.S. Treasury, government, and agency bonds [Member]
12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : U.S. Treasury, government, and agency bonds [Member]
12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate bonds [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled funds [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Cash equivalents and other [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Special situations [Member]
12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Special situations [Member]
12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Real estate investments [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Derivatives [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Post retirement Benefit Plans Defined Benefit [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Private equity [Member]
12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Private equity [Member]
12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Post retirement Benefit Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : U.S. Treasury, government, and agency bonds [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Corporate bonds [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Post retirement Benefit Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled funds [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Post retirement Benefit Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Special situations [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Trust - owned life insurance [Member]
12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Trust - owned life insurance [Member]
12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
12/31/2009
USD ($)
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12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : International [Member]
12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Private equity [Member]
12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Private equity [Member]
12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Private equity [Member]
12/31/2008
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Mortgage and asset backed securities [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Cash equivalents and other [Member]
12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Cash equivalents and other [Member]
12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Pension Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Real estate investments [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2008
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis} : Other Post retirement Benefit Plans Defined Benefit [Member]
{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Private equity [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2008
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)

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12/31/2009
USD ($)

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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Domestic [Member]
12/31/2010
USD ($)

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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Domestic [Member]
12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : International [Member]
12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : International [Member]
12/31/2009
USD ($)

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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Private equity [Member]
12/31/2010
USD ($)

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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Private equity [Member]
12/31/2009
USD ($)

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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Pooled funds [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Derivatives [Member]
12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)

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12/31/2009
USD ($)
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12/31/2010
USD ($)

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12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : International [Member]
12/31/2010
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : International [Member]
12/31/2009
USD ($)
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{us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis} : Private equity [Member]
12/31/2010
USD ($)

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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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USD ($)
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USD ($)
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12/31/2010
USD ($)
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USD ($)
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12/31/2010
USD ($)
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12/31/2009
USD ($)
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