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Stock-Based Compensation - Additional Information (Detail) - USD ($) |  | 12 Months Ended |
--- | --- | --- | ---
Jun. 14, 2020 | Dec. 27, 2020 | Dec. 29, 2019 | Dec. 30, 2018 | May 16, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock-based compensation expense |  | $ 2,515,000 | $ 2,335,000 | $ 2,882,000 |
Stock Options [Member] | Maximum [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Exercisable period from the date of grant |  | 10 years |  |  |
Accounting Standards Update 2016-09 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Shares of common stock reserved for issuance |  |  |  |  | 626,000
Restricted Stock Units (RSUs) [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock units issued |  | 1,604,000 | 402,000 | 131,000 |
Stock-based compensation expense |  | $ 1,500,000 | $ 1,500,000 | $ 1,500,000 |
Unrecognized stock compensation expense |  | $ 1,300,000 |  |  |
Unrecognized stock compensation expense, recognition period |  | 2023 |  |  |
Restricted Stock Units (RSUs) [Member] | Non-Employee Board Of Directors [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Options vesting period |  | 3 years |  |  |
Vesting description |  | The employee grants vest in one-third increments over a three-year period |  |  |
Restricted Stock Units (RSUs) [Member] | First Anniversary [Member] | Non-Employee Board Of Directors [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting percentage |  | 50.00% |  |  |
Restricted Stock Units (RSUs) [Member] | Second Anniversary [Member] | Non-Employee Board Of Directors [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting percentage |  | 50.00% |  |  |
Common Share Options [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock-based compensation expense |  | $ 100,000 | $ 800,000 | $ 1,400,000 |
Unrecognized stock compensation expense |  | $ 100,000 |  |  |
Unrecognized stock compensation expense, recognition period |  | 2022 |  |  |
Performance Stock Units [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock units issued |  | 1,475,000 |  |  |
Options vesting period |  | 5 years |  |  |
Performance Stock Units [Member] | Market Vesting Conditions [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock-based compensation expense |  | $ 900,000 |  |  |
Performance Stock Units [Member] | Performance Vesting Conditions [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock-based compensation expense |  | $ 0 |  |  |
Performance Stock Units [Member] | Maximum [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting percentage of targeted number of shares |  | 200.00% |  |  |
Performance Stock Units [Member] | Minimum [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting percentage of targeted number of shares |  | 0.00% |  |  |
Non-Employee Board Of Directors [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting description |  | The PSUs will vest based on the Company’s achievement of certain targets related to adjusted EBITDA and same store sales goals. The quantity of shares that will vest ranges from 0% to 200% of the targeted number of shares. If the defined minimum targets are not met, then no shares will vest. |  |  |
2019 Long Term Incentive Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Shares of common stock reserved for issuance |  | 2,068,000 |  |  |
Options granted |  | 0 | 0 |  |
Exercise price of options outstanding, lower limit |  | $ 7.22 |  |  |
Exercise price of options outstanding, higher limit |  | $ 20.53 |  |  |
2019 Long Term Incentive Plan [Member] | Maximum [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Options issued and outstanding, last expiration date |  | Dec. 31, 2028 |  |  |
Options vesting period |  | 5 years |  |  |
2019 Long Term Incentive Plan [Member] | Minimum [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Options vesting period |  | 4 years |  |  |
2019 Long Term Incentive Plan [Member] | Common Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Shares of common stock reserved for issuance |  |  |  |  | 1,200,000
Issuance of common stock |  |  | 0 |  |
2019 Long Term Incentive Plan [Member] | Restricted Stock Units (RSUs) [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock units issued |  | 2,908,000 |  |  |
2019 Plan Amanded and Restated [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based compensation arrangement by share-based payment award, number of additional shares authorized | 2,100,000 |  |  |  |
2019 Plan Amanded and Restated [Member] | Common Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based compensation arrangement by share-based payment award, number of additional shares authorized | 900,000 |  |  |  |

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