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Maximum Percentage Of Target Available For Issuance

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate number of common shares reserved for future issuance.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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Unrecognized cost of unvested options awarded to employees as compensation.

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Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

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Amount of the effect of a change in accounting principle on net income.

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The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Restrictions on equity-based instruments during the vesting period, such as the inability to transfer unvested awards, are not taken into account in estimating the fair value of the award. However, restrictions that remain in effect after an award is vested, such as the inability to transfer or hedge vested options or a prohibition on the sale of outstanding vested shares (or other type of equity) for a period of time, affect the estimate of an award's fair value.

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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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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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Percentage of vesting of share-based compensation awards.

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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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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Share-Based Payment Arrangements - Additional Information (Detail)		12 Months Ended
	Apr. 24, 2018 shares	Dec. 29, 2018 USD ($) EquityPlan shares	Dec. 30, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employee equity incentive plans \| EquityPlan		2
Income tax benefit realized on disqualifying dispositions of stock acquired by exercise of incentive stock options		$ 84,000	$ 339,000
Accounting Standards Update 2016-09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax benefit from stock-based awards		$ 2,060,000	$ 1,299,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount rate on stock awards		7.00%
Stock awards granted, shares \| shares	9,324	65,824	67,913	79,948
Recognized share-based compensation expense		$ 15,985,000	$ 5,849,000	$ 849,000
Unrecognized compensation cost expected to be recognized over period, years		3 years 3 months 18 days
Restricted Stock Units (RSUs) \| February 2018 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target available for common share issuance		100.00%
Restricted Stock Units (RSUs) \| February 2017 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target available for common share issuance		100.00%
Restricted Stock Units (RSUs) \| January 2016 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target available for common share issuance		100.00%
Restricted Stock Units (RSUs) \| January 2015 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target available for common share issuance		100.00%
Restricted Stock Units (RSUs) \| April 2018 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage of target available for common share issuance	150.00%
Non Vested Restricted Stock and Deferred Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted, shares \| shares		22,803	42,573	26,033
Unrecognized compensation cost, other than options		$ 3,184,000
Unrecognized compensation cost expected to be recognized over period, years		2 years 2 months 12 days
Directors Stock Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
FMV of restricted shares granted to Directors upon election		$ 110,000	$ 110,000	$ 110,000
Restricted shares granted \| shares		4,950	6,575	7,762
Compensation cost on restricted and Deferred Stock Units granted		$ 660,000	$ 651,000	$ 591,000
Directors Stock Compensation Plan \| Class III Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
FMV of restricted shares granted to Directors upon election		0	0	35,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding, intrinsic value		3,989,000
Intrinsic value of stock options exercisable		3,952,000
Total intrinsic value of stock options exercised during periods		6,715,000	$ 7,599,000	$ 7,427,000
Unrecognized compensation cost, stock options		$ 0
Deferred Stock Units D S Us [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted, shares \| shares		990	1,315
Maximum \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, other than options		$ 18,500,000
Maximum \| Restricted Stock Units (RSUs) \| February 2017 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage of target available for common share issuance		200.00%
Maximum \| Restricted Stock Units (RSUs) \| January 2016 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage of target available for common share issuance		200.00%
Maximum \| Restricted Stock Units (RSUs) \| January 2015 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage of target available for common share issuance		200.00%
Maximum \| Restricted Stock Units (RSUs) \| Prior to 2015 grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage of target available for common share issuance		100.00%
2011 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized for issuance \| shares		6,000,000
Common stock reserved for issuance \| shares		4,436,874
2013 Directors Stock Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized for issuance \| shares		115,000
Common stock reserved for issuance \| shares		72,742
2013 Directors Stock Compensation Plan \| Deferred Stock Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock vesting percentage		100.00%