Employee Benefit Plans - Reclassifications from Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 29, 2018	Sep. 29, 2018
Retirement Benefits [Abstract]
Amortization of actuarial loss - total before tax	$ 185	$ 557
Tax benefit	(45)	(134)
Net of tax	$ 140	$ 423

Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration