Actuarial Assumptions used to Compute Funded Status for U.K. Plan and Japan Plan (Details)	Dec. 31, 2014	Dec. 31, 2013
UNITED KINGDOM
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Weighted-average discount rate	3.50%	4.60%
Rate of inflation	3.60%	2.70%
JAPAN
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Weighted-average discount rate		1.00%
Weighted-average rate of compensation increase		3.00%

Defined benefit plan assumptions used calculating benefit obligation inflation rate.

No definition available.

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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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- Definition

Expected rate of compensation increases (for pay-related plans).

+ 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)(2)

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

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