Income Taxes - Difference Between Tax Provision at Statutory Federal Income Tax Rate and Tax Provision (Detail) - USD ($) $ in Thousands		12 Months Ended
Jan. 02, 2021	Jan. 01, 2022	Jan. 02, 2021
Reconciliation Of Income Taxes [Line Items]
Income tax at the federal statutory rate		$ (4,721)	$ (1,832)
State income taxes, net of federal benefit		4	4
Effect of foreign operations taxed at various rates		48	(235)
Research tax credits		(1,135)	(1,306)
Effect of tax rate changes, permanent differences and adjustments of prior deferrals		6,285	4,461
Unrecognized tax benefits		0	579
Total	$ 1,711	575	1,711
United States
Reconciliation Of Income Taxes [Line Items]
Change in valuation allowance		94	$ 40
Foreign Tax Authority
Reconciliation Of Income Taxes [Line Items]
Change in valuation allowance

Reconciliation Of Income Taxes [Line Items]

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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