Summary of Information Regarding Stock Options (Detail) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 26, 2020 USD ($) $ / shares shares
Number of Options
Beginning Balance, number of options \| shares	44,467
Exercised, number of options \| shares	(23,717)
Ending Balance, number of options \| shares	20,750
Weighted Average Exercise Price per Share
Beginning Balance, Weighted Average Exercise Price per Share \| $ / shares	$ 51.24
Exercised, Weighted Average Exercise Price per Share \| $ / shares	49.31
Ending Balance, Weighted Average Exercise Price per Share \| $ / shares	$ 53.44
Options Exercisable, Number of Options
Options exercisable at the ending, Number of Options \| shares	20,750
Options Exercisable, Weighted Average Exercise Price per Share
Options exercisable at the ending, Weighted Average Exercise Price per Share \| $ / shares	$ 53.44
Weighted Average Remaining Contractual Term (years)
Options outstanding at June 27, 2020	1 year 10 months 24 days
Options exercisable at June 27, 2020	1 year 10 months 24 days
Aggregate Intrinsic Value
Options outstanding at June 27, 2020 \| $	$ 1,499
Options exercisable at June 27, 2020 \| $	$ 1,499

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Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable [Abstract]

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Exercise Price [Abstract]

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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