Retirement Benefit Plans Retirement Benefit Plans - Asset Allocations (Details)	3 Months Ended
Dec. 31, 2011	Dec. 31, 2010
U.S. pension plans [Member]
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]
Cash, real estate and other	11.00%	11.00%
Fixed income securities	54.00%	40.00%
Equity securities	35.00%	49.00%
Actual plan asset allocations	100.00%	100.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation percentage of assets, cash, real estate and other, range minimum	5.00%
Target allocation percentage of assets, cash, real estate and other, range maximum	15.00%
Target allocation percentage of assets, fixed income securities, range minimum	35.00%
Target allocation percentage of assets, fixed income securities, range maximum	55.00%
Target allocation percentage of assets, equity securities, range minimum	35.00%
Target allocation percentage of assets, equity securities, range maximum	55.00%
Non-U.S. pension plans [Member]
Defined Benefit Plan, Actual Plan Asset Allocations [Abstract]
Cash, real estate and other	8.00%	9.00%
Fixed income securities	41.00%	36.00%
Equity securities	51.00%	55.00%
Actual plan asset allocations	100.00%	100.00%
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation percentage of assets, cash, real estate and other, range minimum	7.00%
Target allocation percentage of assets, cash, real estate and other, range maximum	11.00%
Target allocation percentage of assets, fixed income securities, range minimum	31.00%
Target allocation percentage of assets, fixed income securities, range maximum	37.00%
Target allocation percentage of assets, equity securities, range minimum	54.00%
Target allocation percentage of assets, equity securities, range maximum	60.00%

Defined Benefit Plan Cash Real Estate And Other Percent

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- Definition

Defined Benefit Plan Target Allocation Percentage Of Assets Cash Real Estate And Other Range Maximum Percent

+ References

No definition available.

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- Definition

Defined Benefit Plan Target Allocation Percentage Of Assets Cash Real Estate And Other Range Minimum Percent

+ References

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

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.

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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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- Definition

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.

+ Details

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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.

+ Details

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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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