Retirement Benefit Plans (Schedule of assumptions used to determine defined benefit obligations) (Details)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Retirement Plans [Member]
Discount rate	4.92%	5.65%
Expected rate of salary increases	3.34%	3.60%
Future pension/medical cost trend rate increases	3.22%	3.49%
Medical Plan [Member]
Discount rate	4.34%	5.20%
Expected rate of salary increases	3.00%	3.00%
Future pension/medical cost trend rate increases, minimum	5.00%	5.00%
Future pension/medical cost trend rate increases, maximum	8.00%	8.00%

Defined benefit plan, assumptions used calculating benefit obligation, expected rate of salary increases

No definition available.

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- Definition

Defined benefit plan, assumptions used calculating benefit obligation, future pension and medical cost trend rate increases

+ References

No definition available.

+ Details

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- Definition

Defined benefit plan, assumptions used calculating benefit obligation, future pension and medical cost trend rate increases

+ References

No definition available.

+ Details

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- Definition

Defined benefit plan, assumptions used calculating benefit obligation, future pension and medical cost trend rate increases

+ References

No definition available.

+ Details

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- Definition

The interest rate used to adjust for the time value of money for the plan.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph j

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 1

-Subparagraph (k)(1)

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

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