Retirement Benefit Plans (Schedule of assumptions used to determine defined benefit obligations) (Details)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Discount rate	3.60%
Retirement Plans [Member]
Discount rate	3.52%	4.39%
Expected rate of salary increases	3.06%	3.37%
Future pension/medical cost trend rate increases	2.88%	2.85%
Medical Plan [Member]
Discount rate	0.00%	4.70%
Expected rate of salary increases	0.00%	2.50%
Future pension/medical cost trend rate increases, minimum	5.00%	5.00%
Future pension/medical cost trend rate increases, maximum	6.80%	7.20%

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 Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(1)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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