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Maximum Percentage Of Target Available For Issuance

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Number Of Employee Equity Incentive Plans

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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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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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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Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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) $ / shares in Units, $ in Thousands		12 Months Ended
	May 01, 2015 shares	Dec. 31, 2016 USD ($) EquityPlan shares	Dec. 26, 2015 USD ($) shares	Dec. 27, 2014 USD ($) $ / shares shares	Dec. 28, 2013 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		$ 451	$ 383
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		86,572
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		79,948	111,922	146,000
Recognized share-based compensation expense		$ 849	$ 4,943	$ 4,443
Unrecognized compensation cost expected to be recognized over period, years		2 years 7 months 6 days
Stock awards outstanding \| shares		378,238	444,157	425,630	308,007
Restricted Stock Units (RSUs) \| May 2015 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target available for common share issuance	100.00%
Stock awards granted \| shares	20,000
Restricted Stock Units (RSUs) \| January 2016 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU awards vesting period		5 years
Percentage of target available for common share issuance		100.00%
Restricted Stock Units (RSUs) \| Prior to 2016 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU awards vesting period		5 years
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) \| 2012 Grants, Nonvested to Forfeit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, other than options		$ 2,400
Stock awards outstanding \| shares		54,102
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Terms of award		Options granted under the Plans generally become exercisable in either five equal annual installments commencing on the first anniversary of the date of grant or 100% on the fifth anniversary from the date of grant, subject to acceleration in certain circumstances. All options granted under the Plans expire on the tenth anniversary of the date of grant. Under the Plans, the exercise price of each option equals the fair market value of the Company's Common Stock on the date of grant.
The weighted average grant date fair value of stock options granted \| $ / shares				$ 12.70
Stock options outstanding, intrinsic value		$ 13,809
Intrinsic value of stock options exercisable		10,991
Total intrinsic value of stock options exercised during periods		7,427	$ 2,954	$ 14,573
Unrecognized compensation cost		$ 365
Non-vested Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted \| shares		26,033	1,197	7,124
Unrecognized compensation cost, other than options		$ 953
Unrecognized compensation cost expected to be recognized over period, years		1 year 7 months 6 days
Stock awards outstanding \| shares		28,409	18,060	23,353	38,193
Terms of award		The Company's Common Stock on the date of grant. Shares of non-vested restricted stock are generally subject to vesting in three equal annual installments or 100% on the first, third or fifth anniversary of the date of the grant.
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	$ 225
Restricted shares granted \| shares		7,762	1,197	7,124
Compensation cost on restricted shares granted		$ 591	$ 419	$ 331
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		35
Maximum \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, other than options		$ 27,000
Maximum \| Restricted Stock Units (RSUs) \| May 2015 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage of target available for common share issuance	150.00%
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
Other Stock Compensation Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance \| shares		5,000,732