FMV of restricted shares granted to Directors upon election

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Number Of Board Of Director Stock Compensation Plans

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Number Of Employee Equity Incentive Plans

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Share Based Compensation Arrangement By Share Based Payment Award Percentage Used In Calculation To Determine Vesting

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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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-Name Staff Accounting Bulletin (SAB)

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-Section F

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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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- Definition

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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- Definition

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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- Definition

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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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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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 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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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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- Definition

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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- Definition

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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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) (USD $)	12 Months Ended			0 Months Ended
	Dec. 27, 2014 CompensationPlan EquityPlan	Dec. 28, 2013	Dec. 29, 2012	Jan. 23, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employee equity incentive plans	2
Number of board of director stock compensation plans	2
Income tax benefit realized on disqualifying dispositions of stock acquired by exercise of incentive stock options	$ 659,000	$ 502,000
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	$ 12.70	$ 14.21	$ 13.99
Stock options outstanding, intrinsic value	21,264,000
Intrinsic value of stock options exercisable	11,303,000
Total intrinsic value of stock options exercised during periods	14,573,000	6,095,000	12,476,000
Unrecognized compensation cost	2,916,000
Unrecognized compensation cost expected to be recognized over period, years	2 years 2 months 12 days
Non-vested Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Terms of award	Shares of restricted stock generally are granted under the 2011 EIP subject to vesting in three equal annual installments or 100% on the fifth anniversary of the date of grant and the shares of restricted stock remain subject to forfeiture unless the grantee remains continuously employed with the Company or a subsidiary thereof through the applicable vesting date.
Unrecognized compensation cost expected to be recognized over period, years	1 year 10 months 24 days
Unrecognized compensation cost	827,000
Awards issued	7,124	15,449	4,151
2013 Directors Stock Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized for issuance	115,000
Common stock reserved for issuance	95,531
Other Stock Compensation Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance	5,925,501
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost expected to be recognized over period, years	2 years 8 months 12 days
Discount rate on stock awards	7.00%	7.00%	7.00%
Percentage used in calculation to determine vesting	5.00%
Awards issued	146,000	244,500	113,000
Recognized share-based compensation expense	4,443,000	1,276,000	964,000
Restricted Stock Units (RSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	17,100,000
RSU awards vesting period	5 years
Restricted Stock Units (RSUs) \| Chairman and Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards issued				100,000
Restricted Stock Units (RSUs) \| Chairman and Chief Executive Officer \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU awards vesting period				3 years
Directors Stock Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
FMV of restricted shares granted to Directors upon election	225,000
Restricted shares granted	7,124	13,449	4,151
Compensation cost on restricted shares granted	$ 331,000	$ 442,000	$ 292,000