Retirement Plans - Future Benefit Payments (Details) - Pension Plan $ in Thousands	Dec. 31, 2019 USD ($)
United States
Defined Benefit Plan, Expected Future Benefit Payment
2020	$ 429
2021	453
2022	457
2023	481
2024	477
Years 2025-2029	2,276
United Kingdom
Defined Benefit Plan, Expected Future Benefit Payment
2020	280
2021	299
2022	312
2023	370
2024	396
Years 2025-2029	$ 1,744

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108410482&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.

+ References

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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.

+ References

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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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