Income Taxes - Additional Information (Detail) - USD ($)		3 Months Ended	6 Months Ended
Dec. 22, 2017	Jul. 04, 2020	Jun. 29, 2019	Jul. 04, 2020	Jun. 29, 2019
Income Taxes [Line Items]
Income tax expense (benefit)		$ (467,000)	$ 5,113,000	$ 3,671,000	$ 7,398,000
Effective tax rates	25.00%	27.00%	23.10%	17.10%	22.60%
Income tax expense, discrete item			$ 573,000	$ 737,000	$ 1,000,000.0
Refunds of state income taxes		$ 553,000
Effective tax rates, excluding discrete item		21.70%	25.70%	24.60%	25.70%
Payment of estimated federal and state income taxes		$ 0
Federal And State Research And Development Tax Credit [Member]
Income Taxes [Line Items]
Tax credit true-ups to actual from assumptions		$ 319,000

Effective Income Tax Rate Continuing Operations Excluding Effect Of Temporary Differences

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Income tax expense discrete item.

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Income taxes.

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

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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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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 revisions of previously reported income tax expense (benefit).

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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The amount of cash received during the period as refunds for the overpayment of taxes.

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