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

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- Definition

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

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- Definition

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

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- Definition

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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- Definition

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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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 shares authorized for issuance under share-based payment arrangement.

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- Definition

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

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No definition available.

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- Definition

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

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- Definition

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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Amount of noncash expense for option under share-based payment arrangement.

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Stock-Based Compensation - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
	May 31, 2017	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation cost related to stock options		$ 300,000	$ 200,000	$ 800,000	$ 500,000
Stock options granted				109,352
Stock options exercised				6,630
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		0	0	10,735	13,669
Compensation cost		$ 100,000	$ 100,000	$ 300,000	$ 200,000
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		1,000,000.0	$ 800,000	3,000,000.0	2,300,000
Unrecognized compensation cost related to non-vested stock options		7,900,000		$ 7,900,000
Unrecognized compensation cost related to nonvested stock options, weighted-average period				2 years 6 months
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock options		$ 2,700,000		$ 2,700,000
Unrecognized compensation cost related to nonvested stock options, weighted-average period				2 years 10 months 24 days
Capitalized compensation cost				$ 0	$ 0
Stock options granted				109,352	38,670
Stock options exercised				6,630	35,401
Tax benefit generated from compensation cost and credited				$ 0	$ 0