Retirement Plans (Future Benefit Payments) (Details) - Pension Plan $ in Thousands	Dec. 31, 2018 USD ($)
United States
Defined Benefit Plan, Expected Future Benefit Payment
2019	$ 940
2020	946
2021	1,004
2022	1,021
2023	1,080
Years 2024-2028	5,396
United Kingdom
Defined Benefit Plan, Expected Future Benefit Payment
2019	261
2020	276
2021	283
2022	301
2023	325
Years 2024-2028	$ 2,044

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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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