Expiration of California enterprise zone credits.

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Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Jan. 03, 2023	Dec. 28, 2021	Dec. 29, 2020	Dec. 31, 2019
Significant Change In Unrecognized Tax Benefits Is Reasonably Possible [Line Items]
Income tax credit carryforwards	$ 56,780,000	$ 41,826,000
Net operating losses	7,347,000	5,569,000
Valuation allowances against net operating loss and tax credit carryforwards	1,151,000	586,000
Accrued penalties and interest to uncertain tax positions	100,000	100,000
Unrecognized tax benefits	1,249,000	1,198,000	$ 1,333,000	$ 1,345,000
Unrecognized tax benefits that would impact effective tax rate, if reversed	1,100,000
Anticipated decrease in liability for unrecognized tax benefits within next twelve-month period	0
Federal
Significant Change In Unrecognized Tax Benefits Is Reasonably Possible [Line Items]
Income tax credit carryforwards	$ 55,900,000
Tax credits expiration year	2038
Valuation allowances against net operating loss and tax credit carryforwards	$ 0	0
Federal \| Earliest Tax Year
Significant Change In Unrecognized Tax Benefits Is Reasonably Possible [Line Items]
Income tax examination, years open	2015
State or Local Taxing Jurisdiction
Significant Change In Unrecognized Tax Benefits Is Reasonably Possible [Line Items]
Income tax credit carryforwards	$ 800,000
Tax credits expiration year	2023
Valuation allowances against net operating loss and tax credit carryforwards	$ 1,200,000	$ 600,000
State or Local Taxing Jurisdiction \| Earliest Tax Year
Significant Change In Unrecognized Tax Benefits Is Reasonably Possible [Line Items]
Income tax examination, years open	2018
Expiration Periods Beginning 2023
Significant Change In Unrecognized Tax Benefits Is Reasonably Possible [Line Items]
Federal net operating loss	$ 4,000,000.0
State net operating losses	$ 142,800,000