Date of plan approval.

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Maximum grant period from date of plan approval.

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Percentage of discount upon stock to be issued under employee stock purchase plans.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost capitalized for award under share-based payment arrangement.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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 cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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

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Amount of cost expensed and capitalized for award under share-based payment arrangement.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Number of share options (or share units) exercised during the current period.

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Stock-Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019	May 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized number of common stock shares for grant	1,200,000		1,200,000
Date of plan approval			May 16, 2018
Maximum grant period from date of plan approval			10 years
Shares available for grant under the plan	856,921		856,921
Compensation cost related to stock options	$ 300,000	$ 200,000	$ 500,000	$ 300,000
Stock options granted			102,584
Stock options exercised			419
Cash generated from stock option exercises under the plan			$ 0
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized number of common stock shares for grant					1,000,000
Rate of discount on shares of common stock available for sale to eligible employees			15.00%
Number of shares purchased	10,735	13,669	10,735	13,669
Compensation cost	$ 100,000	$ 100,000	$ 200,000	$ 200,000
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash generated from stock option exercises under the plan				100,000
Restricted Stock and Restricted Stock Units Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost related to restricted stock	1,100,000	$ 800,000	2,000,000.0	1,500,000
Unrecognized compensation cost related to non-vested stock options	9,600,000		$ 9,600,000
Unrecognized compensation cost related to nonvested stock options, weighted-average period			2 years 8 months 12 days
Tax benefit generated from compensation cost and credited				200,000
Restricted Stock and Restricted Stock Units Award [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax benefit generated from compensation cost and credited			$ 100,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock options	$ 3,600,000		$ 3,600,000
Unrecognized compensation cost related to nonvested stock options, weighted-average period			3 years 1 month 6 days
Tax benefit generated from compensation cost and credited			$ 0	0
Capitalized compensation cost			$ 0	$ 0
Stock options granted			102,584	36,235
Stock options exercised			419	34,301