Postretirement Benefit Plans - Estimated Future Benefit Payments (Detail) $ in Thousands	Dec. 31, 2020 USD ($)
United States [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
2021	$ 8,744
2022	9,118
2023	9,505
2024	9,820
2025	10,033
2026-2030	51,138
United Kingdom [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
2021	535
2022	557
2023	600
2024	631
2025	659
2026-2030	$ 3,893

Pension plans postretirement and other employee benefits.

No definition available.

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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

+ Details

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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

+ Details

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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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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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