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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for 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 cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for 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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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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Number of shares authorized for issuance under share-based payment arrangement.

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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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Description of terms of award under share-based payment arrangement.

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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
	Dec. 25, 2021	Dec. 26, 2020	Dec. 28, 2019
Accounting Standards Update 2016-09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax benefit from stock-based awards	$ 1,057,000	$ 941,000	$ 3,019,000
February 2021 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target available for common share issuance	100.00%
February 2020 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target available for common share issuance		100.00%
February 2019 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)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage of target available for common share issuance	150.00%
Discount rate on stock awards	7.00%
Stock awards granted, shares	46,342	59,967	68,820
Recognized share-based compensation expense	$ 24,197,000	$ 1,602,000	$ 1,557,000
Unrecognized compensation cost, other than options	$ 18,300,000
Unrecognized compensation cost expected to be recognized over period, years	3 years 3 months 18 days
Non Vested Restricted Stock and Deferred Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted, shares	26,351	26,604	30,338
Unrecognized compensation cost, other than options	$ 3,880,000
Unrecognized compensation cost expected to be recognized over period, years	1 year 10 months 24 days
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 either on the first, second and third anniversary of the date of grant or the third, fourth and fifth anniversary of the date of the grant, or 100% on the first or fifth anniversary of the date of the grant. For restricted stock awards granted under the 2013 DSCP plan, each recipient may elect to defer receipt of shares and instead receive restricted stock units (“Deferred Stock Units”), which represent contingent rights to receive shares of the Company’s Common Stock on the date of recipient separation
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	4,890	5,240
Compensation cost on restricted and Deferred Stock Units granted	$ 669,000	$ 660,000	660,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding, intrinsic value	1,001,000
Total intrinsic value of stock options exercised during periods	965,000	$ 1,846,000	$ 2,683,000
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	978	1,048
Maximum \| Restricted Stock Units (RSUs) \| February 2021 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) \| February 2020 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) \| February 2019 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	6,000,000
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	56,782
2013 Directors Stock Compensation Plan \| Deferred Stock Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock vesting percentage	100.00%
Other Stock Compensation Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance	3,502,816
Market Condition \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted, shares			9,725