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

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Current assets (normally turning over within one year or one business cycle if longer) that are held for sale apart from normal operations and anticipated to be sold within one year.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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Amount of acquisition 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 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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The value of all consideration given or received by the Entity in the significant acquisition or disposal.

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Property and Equipment (Details) (USD $)	12 Months Ended			0 Months Ended
Property and Equipment (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 31, 2012
Property, Plant and Equipment [Line Items]
Property and equipment, net	$ 161,773,000us-gaap_PropertyPlantAndEquipmentNet	$ 141,923,000us-gaap_PropertyPlantAndEquipmentNet
Depreciation expense	23,500,000us-gaap_Depreciation	21,100,000us-gaap_Depreciation	21,500,000us-gaap_Depreciation
Impairment loss on assets held-for-sale		2,000,000
Proceeds from sale of productive assets	500,000
Asset held for sale	375,000us-gaap_AssetsHeldForSaleCurrent	417,000us-gaap_AssetsHeldForSaleCurrent
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	39,874,000	14,793,000
Depreciable Assets [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	277,901,000	268,793,000
Less: accumulated depreciation	(161,276,000)	(144,121,000)
Property and equipment, net	116,625,000	124,672,000
Automobiles and trucks
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	2,006,000	2,148,000
Building and improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	28,641,000	22,828,000
Construction equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	146,088,000	145,309,000
Dredges and dredging equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	96,275,000	93,963,000
Office equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	4,891,000	4,545,000
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	5,274,000	2,458,000
Purchase of the assets of West Construction
Property, Plant and Equipment [Line Items]
Purchase price of significant acquisitions during period				9,300,000
Fixed assets increase due to acquisition				$ 4,500,000