Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unrecognized tax benefits.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jul. 03, 2018	Jan. 02, 2018	Jul. 04, 2017	Jan. 03, 2017
Significant Change In Unrecognized Tax Benefits Is Reasonably Possible [Line Items]
Corporate marginal tax rate	21.00%	35.00%
Unrecognized tax benefits	$ 1,560	$ 1,516	$ 1,309	$ 1,245
Unrecognized tax benefits that would impact effective tax rate, if reversed	$ 1,100
Federal \| Earliest Tax Year
Significant Change In Unrecognized Tax Benefits Is Reasonably Possible [Line Items]
Income tax examination, years open	2014
State or Local Taxing Jurisdiction \| Earliest Tax Year
Significant Change In Unrecognized Tax Benefits Is Reasonably Possible [Line Items]
Income tax examination, years open	2013