Retirement Plans - Future Benefit Payments (Details) - Pension Plan $ in Thousands	Dec. 31, 2020 USD ($)
United States
Defined Benefit Plan, Expected Future Benefit Payment
2021	$ 468
2022	467
2023	491
2024	487
2025	478
Years 2026-2030	2,255
United Kingdom
Defined Benefit Plan, Expected Future Benefit Payment
2021	306
2022	318
2023	377
2024	404
2025	429
Years 2026-2030	$ 1,844

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

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

+ References

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- Definition

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

+ References

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

+ References

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

+ References

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

+ References

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