Retirement Plans (Benefit Payments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months	$ 793
Defined Benefit Plan, Expected Future Benefit Payments, Year Two	822
Defined Benefit Plan, Expected Future Benefit Payments, Year Three	882
Defined Benefit Plan, Expected Future Benefit Payments, Year Four	915
Defined Benefit Plan, Expected Future Benefit Payments, Year Five	993
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter	5,606
United Kingdom Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months	246
Defined Benefit Plan, Expected Future Benefit Payments, Year Two	270
Defined Benefit Plan, Expected Future Benefit Payments, Year Three	288
Defined Benefit Plan, Expected Future Benefit Payments, Year Four	307
Defined Benefit Plan, Expected Future Benefit Payments, Year Five	334
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter	$ 1,965

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Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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 (f)

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

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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