Schedule of Income Taxes Calculated on Income from Continuing Operations Before Income Taxes and Provision for Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Income Tax Disclosure [Line Items]
Income taxes at federal income tax rate	$ 77,418	$ 60,683	$ 69,170
State income taxes, net of federal income tax benefit	4,532	3,260	1,486
Meals and entertainment exclusion	777	919	919
Share-based payments	(239)	184	(122)
Other, net	(102)	(589)	(390)
Income taxes	$ 82,386us-gaap_IncomeTaxExpenseBenefit	$ 64,457us-gaap_IncomeTaxExpenseBenefit	$ 71,063us-gaap_IncomeTaxExpenseBenefit

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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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

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-Glossary Income Tax Expense (or Benefit)

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-Name Accounting Standards Codification

-Topic 740

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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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-Publisher FASB

-Name Accounting Standards Codification

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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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