Schedule for Gross Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017
Income Tax Disclosure [Line Items]
Gross unrecognized tax benefits - beginning of the year	$ 4,812	$ 2,635
Gross increases related to current year tax positions	714	645
Gross increases related to prior year tax positions	370	2,189
Gross decreases related to prior year tax positions	(1,575)	(75)
Settlements	(159)	(100)
Lapse of statute of limitations	(643)	(482)
Gross unrecognized tax benefits - end of the year	$ 3,519	$ 4,812

Income Tax Disclosure [Line Items]

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Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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