Postretirement Benefit Plans - Estimated Future Benefit Payments (Detail) $ in Thousands	Dec. 31, 2018 USD ($)
United States [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
2019	$ 8,009
2020	8,443
2021	8,954
2022	9,438
2023	9,836
2024-2028	51,998
United Kingdom [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
2019	482
2020	487
2021	509
2022	553
2023	592
2024-2028	$ 3,557

Pension plans postretirement and other employee benefits.

No definition available.

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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

+ Details

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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.

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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