Property and Equipment, Net (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012
Property, Plant and Equipment [Line Items]
Property and equipment	$ 1,218,640	$ 1,216,298	$ 1,171,236
Accumulated depreciation and depletion	747,375	734,820	731,572
Property and equipment, net	471,265	481,478	439,664
Equipment and vehicles [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	760,271	758,782	722,724
Quarry property [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	180,325	180,567	177,792
Land and land improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	125,489	125,961	126,396
Building and leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	83,733	83,245	80,910
Office furniture and equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	$ 68,822	$ 67,743	$ 63,414

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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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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- Definition

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.

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