Retirement Plans (Benefit Payments) (Details) - Pension Plan $ in Thousands	Dec. 31, 2017 USD ($)
UNITED STATES
Defined Benefit Plan, Expected Future Benefit Payment
2018	$ 927
2019	996
2020	1,003
2021	1,058
2022	1,071
Years 2023-2027	5,608
Foreign Plan
Defined Benefit Plan, Expected Future Benefit Payment
2018	259
2019	275
2020	291
2021	299
2022	317
Years 2023-2027	$ 2,040

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- Definition

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ 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=82843861&loc=d3e1928-114920

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- Definition

Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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- Definition

Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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