Amounts Recognized in Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan [Abstract]
Noncurrent liability	$ (6,473)	$ (6,774)
Accumulated Other Comprehensive loss, net of taxes	$ 860	$ 919

Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Publisher FASB
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant