Schedule of Deferred Tax Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 27, 2014	Dec. 28, 2013
Income Tax Disclosure [Line Items]
Receivable valuations	$ 3,623	$ 3,354
Share-based payments	2,939	3,458
Self-insured claims	5,353	5,180
Other	3,616us-gaap_DeferredTaxAssetsOther	3,863us-gaap_DeferredTaxAssetsOther
Total deferred tax assets	15,531us-gaap_DeferredTaxAssetsNet	15,855us-gaap_DeferredTaxAssetsNet
Operating property	46,745	41,933
Goodwill	5,619	5,553
Other	2,192us-gaap_DeferredTaxLiabilitiesOther	1,960us-gaap_DeferredTaxLiabilitiesOther
Total deferred tax liabilities	54,556us-gaap_DeferredTaxLiabilities	49,446us-gaap_DeferredTaxLiabilities
Net deferred tax liability	$ 39,025us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 33,591us-gaap_DeferredTaxAssetsLiabilitiesNet

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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