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Income Taxes - Additional Information (Detail) - USD ($) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 27, 2020 | Dec. 29, 2019 | Dec. 30, 2018 | Mar. 27, 2020 | Mar. 31, 2019
Income Tax [Line Items] |  |  |  |  |
Income tax expense (benefit) | $ (6,536,000) | $ 14,190,000 | $ (2,195,000) |  |
Net operating loss carryforwards | 14,364,000 | 3,721,000 |  |  |
Deferred tax assets, valuation allowance | 30,381,000 | 16,116,000 |  |  | $ 13,600,000
Unrecognized tax benefits, income tax penalties and interest accrued | 0 | 0 |  |  |
Uncertain tax positions | 0 | 0 |  |  |
Valuation Allowance Tax Credit Carryforward [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Deferred tax assets, valuation allowance | 30,400,000 | 16,100,000 |  |  |
Federal and State Income Tax [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Net operating loss carryforwards | 14,300,000 | $ 3,700,000 |  |  |
COVID 19 [Member] |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |
Tax refund from net operating loss carryback |  |  |  | $ 6,700,000 |
Income tax expense (benefit) | $ 6,700,000 |  |  |  |

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