Pensions and Postretirement Benefits (Details 9) (U.S. Plans [Member])	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Target asset allocation and actual asset allocations for US Pension Plans
Target Allocation 2012	100.00%
Actual asset allocation, Total	100.00%	100.00%
Equity Securities [Member]
Target asset allocation and actual asset allocations for US Pension Plans
Target Allocation 2012 Minimum	35.00%
Target Allocation 2012 Maximum	65.00%
Actual asset allocation	45.00%	62.00%
Fixed Income Funds [Member]
Target asset allocation and actual asset allocations for US Pension Plans
Defined Benefit Plan, Target Allocation Percentage of Assets, Debt Securities, Range Minimum	30.00%
Defined Benefit Plan, Target Allocation Percentage of Assets, Debt Securities, Range Maximum	60.00%
Defined Benefit Plan, Debt Securities	43.00%	31.00%
Cash [Member]
Target asset allocation and actual asset allocations for US Pension Plans
Defined Benefit Plan, Target Allocation Percentage of Assets, Other, Range Minimum	0.00%
Defined Benefit Plan, Target Allocation Percentage of Assets, Other, Range Maximum	2.00%
Defined Benefit Plan, Other Plan Assets	1.00%	1.00%
Equities U.S. Large Cap [Member]
Target asset allocation and actual asset allocations for US Pension Plans
Target Allocation 2012 Minimum	15.00%
Target Allocation 2012 Maximum	35.00%
Actual asset allocation	24.00%	31.00%
Equities U.S. Mid Cap [Member]
Target asset allocation and actual asset allocations for US Pension Plans
Target Allocation 2012 Minimum	3.00%
Target Allocation 2012 Maximum	8.00%
Actual asset allocation	4.00%	7.00%
Equities U S Small Cap [Member]
Target asset allocation and actual asset allocations for US Pension Plans
Target Allocation 2012 Minimum	1.00%
Target Allocation 2012 Maximum	6.00%
Actual asset allocation	2.00%	4.00%
Equities Developing International & Emerging Markets [Member]
Target asset allocation and actual asset allocations for US Pension Plans
Target Allocation 2012 Minimum	10.00%
Target Allocation 2012 Maximum	20.00%
Actual asset allocation	15.00%	20.00%
Equities & Alternatives [Member]
Target asset allocation and actual asset allocations for US Pension Plans
Target Allocation 2012 Minimum	45.00%
Target Allocation 2012 Maximum	70.00%
Actual asset allocation	56.00%	68.00%
Real Estate Commingled Funds [Member]
Target asset allocation and actual asset allocations for US Pension Plans
Defined Benefit Plan, Target Allocation Percentage of Assets, Real Estate, Range Minimum	0.00%
Defined Benefit Plan, Target Allocation Percentage of Assets, Real Estate, Range Maximum	10.00%
Defined Benefit Plan, Real Estate	8.00%	5.00%
Commodity [Member]
Target asset allocation and actual asset allocations for US Pension Plans
Defined Benefit Plan, Target Allocation Percentage of Assets, Other, Range Minimum	2.00%
Defined Benefit Plan, Target Allocation Percentage of Assets, Other, Range Maximum	4.00%
Defined Benefit Plan, Other Plan Assets	3.00%	1.00%

Defined Benefit Plan Target Allocation Percentage of Assets.

No definition available.

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- Definition

The percentage of the fair value of debt securities to the fair value of total plan assets held as of the measurement date.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(1)

-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 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2446-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

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- Definition

The percentage of the fair value of equity securities to the fair value of total plan assets held as of the measurement date.

+ References

+ Details

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- Definition

The percentage of the fair value of investments other than debt securities, equity securities, and real estate to the fair value of total plan assets held as of the measurement date.

+ References

+ Details

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- Definition

The percentage of the fair value of real estate to the fair value of total plan assets held as of the measurement date.

+ References

+ Details

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- Definition

Target allocation maximum percentage of investments in debt securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

+ Details

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- Definition

Target allocation minimum percentage of investments in debt securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(2)

-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 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(i)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2446-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(i)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

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Target allocation maximum percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

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- Definition

Target allocation minimum percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

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- Definition

Target allocation maximum percentage in other than debt securities, equity securities, and real estate to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

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Target allocation minimum percentage in other than debt securities, equity securities, and real estate to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

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- Definition

Target allocation maximum percentage of investments in real estate to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

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Target allocation minimum percentage of investments in real estate to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

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- Definition

The aggregate percentage of the fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of total plan assets held as of the measurement date.

+ References

+ Details

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