Property and Equipment - Components of Property and Equipment, Net (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Property Plant And Equipment [Line Items]
Total, at cost	$ 1,115,936us-gaap_PropertyPlantAndEquipmentGross	$ 1,006,147us-gaap_PropertyPlantAndEquipmentGross
Less accumulated depreciation	(316,617)	(300,035)
Subtotal	799,319	706,112
Less assets held for sale		(4,101)
Property and Equipment, net	799,319us-gaap_PropertyPlantAndEquipmentNet	702,011us-gaap_PropertyPlantAndEquipmentNet
Land [Member]
Property Plant And Equipment [Line Items]
Total, at cost	224,124	194,639
Building and Improvements [Member]
Property Plant And Equipment [Line Items]
Total, at cost	582,261	569,619
Office Equipment and Fixtures [Member]
Property Plant And Equipment [Line Items]
Total, at cost	151,165	135,221
Parts and Service Equipment [Member]
Property Plant And Equipment [Line Items]
Total, at cost	68,248	70,950
Company Vehicles [Member]
Property Plant And Equipment [Line Items]
Total, at cost	8,958	8,002
Construction in Progress [Member]
Property Plant And Equipment [Line Items]
Total, at cost	$ 81,180	$ 27,716

Property plant and equipment including assets held for sale net.

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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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Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of.

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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.

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