Contractual term of option.

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- Definition

Options granted since inception of the plan.

+ References

No definition available.

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- Definition

Fiscal year through which the Company expects to recognize the cost of unvested options awarded to employees that have been granted as of the balance sheet date.

+ References

No definition available.

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- Definition

Vesting percentage of targeted number of shares.

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Aggregate number of common shares reserved for future issuance.

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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- Definition

Amount of noncash expense for share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Date the equity-based award expires, in CCYY-MM-DD format.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Percentage of vesting of award under share-based payment arrangement.

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Number of new stock issued during the period.

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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