Schedule of Expected Benefit Payments (Detail) - Pension Plans, Defined Benefit $ in Thousands	Dec. 31, 2018 USD ($)
Schedule of Pension Expected Future Benefit Payments [Line Items]
2019	$ 6,314
2020	6,286
2021	6,251
2022	6,222
2023	6,199
2024 – 2028	31,307
Total 10-year estimated future benefit payments	$ 62,579

Defined benefit plan, expected future benefit payments.

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- Definition

Schedule of Pension Expected Future Benefit Payments [Line Items]

+ References

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.

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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.

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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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- Definition

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

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- Definition

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

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- Definition

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

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