Income Taxes - Tax Effect of Temporary Differences and Carryforwards that Give Rise to Significant Portions of the Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Jan. 01, 2022	Jan. 02, 2021
Tax effect of temporary differences and carryforwards that give rise to significant portions of the net deferred tax assets
Net operating losses	$ 13,751	$ 11,769
Research and development credits	3,582	3,273
Accruals and reserves	2,637	2,382
Deferred revenue	82	81
Property and equipment	361	307
Intangible assets	268	328
Stock compensation	574	658
Net deferred tax asset	21,255	18,798
Valuation allowance	(21,280)	(18,820)
Net deferred tax liabilities	$ (25)	$ (22)

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from in-process research and development costs expensed in connection with a business combination.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from reserves and accruals.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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