Property and Equipment, Net (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Property, Plant, and Equipment Disclosure [Line Items]
Land	$ 1,131	$ 1,388
Buildings and improvements	48,457	42,408
Machinery, vehicles and equipment	57,130	52,636
Furniture and fixtures	18,251	15,049
Property and equipment, gross	124,969	111,481
Less: accumulated depreciation and amortization	(82,127)	(72,026)
Property and equipment, net	$ 42,842	$ 39,455

The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Gross amount, at the balance sheet date, of long-lived, depreciable assets commonly used in offices and stores. Examples include desks, chairs, and store fixtures.

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- Definition

Carrying amount as of the balance sheet date of real estate held for productive use. This excludes land held for sale.

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- Definition

Gross amount, as of the balance sheet date, of long-lived, depreciable assets used in the production process to produce goods and services.

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Gross amount of long-lived 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, furniture and fixtures, and computer equipment.

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Amount, net of accumulated depreciation, depletion and amortization, of long-lived 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, furniture and fixtures, and computer equipment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 7

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