Schedule of Income Taxes Calculated on Income from Continuing Operations Before Income Taxes and Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Income Tax Disclosure [Line Items]
Income taxes at federal income tax rate	$ 52,289	$ 62,110	$ 68,960
State income taxes, net of federal income tax benefit	5,375	8,876	7,713
Non-deductible executive compensation	96		1,012
Meals and entertainment exclusion	326	644	719
Share-based payments	(977)	(3,093)	(2,138)
Section 199 deductions and R&D credits	(717)	(714)	(3,309)
Other, net	499	237	211
Income taxes	$ 56,891	$ 68,060	$ 73,168

Income Tax Disclosure [Line Items]

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Income Tax Reconciliation Section 199 Deductions And Research And Development Credits

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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