Employee Benefit Plans - Future Benefit Payments Under Pension Plans (Detail) $ in Thousands	Dec. 31, 2018 USD ($)
Pension Plan
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2019	$ 1,206
2020	1,282
2021	1,378
2022	1,479
2023	1,522
2024 - 2028	8,741
Retirement Plan \| La Barge
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2019	581
2020	561
2021	538
2022	512
2023	483
2024 - 2028	$ 1,991

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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.

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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.

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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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