Common stock held by relatives of director percentage.

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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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Stock repurchased and retired during period average purchase price.

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Term of compensation on compound annual growth in pre-tax income.

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Aggregate number of common shares reserved for future issuance.

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Unrecognized cost of unvested share-based compensation awards.

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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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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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

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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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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Capital Stock - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	May 31, 2017	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016	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%
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		1,162,398
Compensation cost related to restricted stock		$ 2,600,000	$ 2,800,000	$ 2,300,000
Compensation cost related to stock options		$ 500,000	$ 300,000	$ 100,000
Weighted-average grant-date fair value		$ 73.84	$ 78.58	$ 44.36
Cash received from stock option exercises under the plan		$ 201,000	$ 31,000
Stock options exercised		15,113	32,751
Total 401(K) expense		$ 4,300,000	$ 2,700,000	$ 2,500,000
Common stock, shares held by 401(K) plan		243,348
Repurchase and cancellation of shares		26,280	19,110	38,970
Common stock repurchased, average price		$ 74.79	$ 73.34	$ 56.66
Common stock repurchased, value		$ 2,000,000	$ 1,400,000	$ 2,200,000
Share Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock repurchased, average price		$ 69.73	$ 74.26	$ 52.15
Common stock repurchased, value		$ 43,400,000	$ 74,700,000	$ 22,500,000
Share repurchase program shares authorized to be repurchased					$ 400,000,000	$ 10,000,000
Share repurchase program shares authorized to be repurchased expiration date		Dec. 31, 2021
Shares repurchased under share repurchase program		622,223	1,006,365	430,866
Authorized date of repurchase of outstanding common stock		Dec. 12, 2013
Shares available for repurchase under share repurchase program		183,300,000
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		21,173	0
Compensation cost		$ 400,000	$ 100,000
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash received from stock option exercises under the plan			100,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Capitalized compensation cost		0	0	$ 0
Unrecognized compensation cost related to non-vested stock options		$ 5,900,000
Unrecognized compensation cost related to nonvested stock options, weighted-average period		2 years 3 months 18 days
Tax benefit generated from compensation cost and credited		$ 100,000	400,000	300,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Capitalized compensation cost		0	0	0
Unrecognized compensation cost related to non-vested stock options		$ 1,800,000
Unrecognized compensation cost related to nonvested stock options, weighted-average period		2 years 9 months 18 days
Tax benefit generated from compensation cost and credited		$ 0	$ 600,000	$ 0
Weighted-average grant-date fair value		$ 15.88	$ 15.81	$ 8.40
Stock options exercised				0
Performance-Based Long Term Award Program [Member] \| Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of compensation on compound annual growth in our pre-tax income		3 years