Actuarial Assumptions used to Compute Benefit Obligations (Details) - UNITED KINGDOM	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Weighted-average discount rate	2.60%	3.80%
Rate of inflation	3.00%	2.80%

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

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=65897934&loc=d3e1928-114920

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