Equity-Based Compensation - Additional information (Detail) - USD ($)	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of option price related to fair market value	100.00%
Common stock shares authorized for further issuance	6,500,000
2012 plan options expiration date	May 08, 2022
Purchase of common stock through payroll deductions	85.00%
Offering periods	2 years
Maximum employee salary withholdings for purchase of common stock under the terms of the ESPP	15.00%
Purchase intervals of a series	6 months
Total intrinsic value of options exercised	$ 249,000	$ 431,000
Total unrecognized compensation expense	$ 895,000
RSU conversion ratio	100.00%
Options granted under performance stock options	372,500
Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted under performance stock options	37,500
Performance stock option vesting period	1 year 1 month 6 days
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, expiration period	10 years
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available under issuance of ESPP	555,000
Total unrecognized compensation expense	$ 156,000
Unrecognized compensation expenses recognition period	6 months
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expenses recognition period	1 year 3 months 21 days
Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period	3 years
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period	4 years
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expenses recognition period	1 year 3 months 18 days
Unrecognized compensation expense	$ 1,500,000
Restricted Stock Units (RSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period	3 years
Restricted Stock Units (RSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period	4 years

Exercise price of share options as percentage of fair market value minimum.

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Maximum employee salary withholdings for purchase of common stock under the terms of the ESSP.

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Share-based compensation arrangement by share-based payment award, award conversion ratio.

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Share-based compensation arrangement by share-based payment award options offering period.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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

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

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Gross number of share options (or share units) granted during the period.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Purchase price of common stock expressed as a percentage of its fair value.

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