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Date of plan approval.

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Maximum grant period from date of plan approval.

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Number of common stock held under retirement plan.

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

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Stock Repurchase Program Approval Date

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Aggregate number of common shares reserved for future issuance.

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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 cost (reversal of cost) for pension and other postretirement benefits.

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

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Amount of noncash expense for award of restricted stock or unit 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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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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

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Amount of stock repurchase plan authorized.

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Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the CCYY-MM-DD format.

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The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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Capital Stock - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	May 31, 2017	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018	Dec. 26, 2015	Dec. 27, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of outstanding shares owned by controlling family		18.00%	18.00%
Shares authorized of undesignated capital stock for future issuance		50,000,000
Authorized number of common stock shares for grant		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		853,471
Weighted-average grant-date fair value		$ 63.25	$ 81.84	$ 73.84
Compensation cost related to stock options		$ 1,000,000.0	$ 700,000	$ 500,000
Cash received from stock option exercises under the plan		1,184,000	123,000	201,000
Total 401(K) expense		$ 3,600,000	$ 3,100,000	$ 4,300,000
Common stock, shares held by 401(K) plan		195,368
Share Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share repurchase program shares authorized to be repurchased					$ 500,000,000	$ 10,000,000
Share repurchase program shares authorized to be repurchased expiration date		Dec. 31, 2022
Authorized date of repurchase of outstanding common stock		Dec. 12, 2013
Shares available for repurchase under share repurchase program		207,100,000
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		79,089	21,200	21,173
Compensation cost		$ 3,300,000	$ 300,000	$ 400,000
Tax benefit generated from compensation cost		$ 500,000	0	0
Performance-Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value		$ 65.09
Performance-based and Time-based Restricted Stock Awards and Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost related to restricted stock awards and restricted stock units		$ 3,200,000	2,100,000	2,600,000
Capitalized compensation cost		0	$ 0	$ 0
Restricted Stock Awards And Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to unvested stock options		$ 6,900,000
Unrecognized compensation cost related to unvested stock options, weighted-average period		2 years 3 months 18 days
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value		$ 17.84	$ 24.32	$ 15.88
Capitalized compensation cost		$ 0	$ 0	$ 0
Unrecognized compensation cost related to unvested stock options		$ 2,300,000
Unrecognized compensation cost related to unvested stock options, weighted-average period		2 years 9 months 18 days