Operating Property (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 27, 2014	Dec. 28, 2013
Property, Plant and Equipment [Line Items]
Land	$ 9,148us-gaap_Land	$ 9,148us-gaap_Land
Buildings and improvements	38,790us-gaap_BuildingsAndImprovementsGross	33,160us-gaap_BuildingsAndImprovementsGross
Trailing equipment	267,685lstr_TrailingEquipmentGross	245,430lstr_TrailingEquipmentGross
Other equipment	47,261us-gaap_PropertyPlantAndEquipmentOther	47,576us-gaap_PropertyPlantAndEquipmentOther
Total operating property, gross	362,884us-gaap_PropertyPlantAndEquipmentGross	335,314us-gaap_PropertyPlantAndEquipmentGross
Less accumulated depreciation and amortization	160,681	157,985
Total operating property, net	$ 202,203us-gaap_PropertyPlantAndEquipmentNet	$ 177,329us-gaap_PropertyPlantAndEquipmentNet

Trailing Equipment, Gross

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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- Definition

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

+ References

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale.

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