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Represents the number of division whose assets and liabilities are transferred to PES entity.

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Represents the percentage of ownership interest of the entity.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The net result for the period of deducting operating expenses from operating revenues.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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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 of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Nature of Business (Details) (USD $)	3 Months Ended		1 Months Ended	3 Months Ended	0 Months Ended		12 Months Ended
Nature of Business (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Jun. 30, 2014	Sep. 30, 2014 item	Feb. 28, 2015	Jan. 22, 2014	Dec. 31, 2014
Nature of Business
Operating income	$ 4,245,000us-gaap_OperatingIncomeLoss	$ 20,045,000us-gaap_OperatingIncomeLoss
Goodwill	128,727,000us-gaap_Goodwill						119,410,000us-gaap_Goodwill
Vadnais Corporation
Nature of Business
Amount of purchase of assets and liabilities			6,354,000
Surber, Ram-Fab and Williams
Nature of Business
Amount of purchase of assets and liabilities				8,200,000
Number of small purchases made				3
Primoris AV
Nature of Business
Cash payment made					23,000,000
Current assets					4,000,000
Current liabilities					2,300,000
Plant and equipment					11,200,000
Goodwill					9,300,000
Blythe
Nature of Business
Ownership percentage	50.00%
BWP \| Blaus Wasser, LLC
Nature of Business
Amount of purchase of assets and liabilities						5,000,000
Capitalized property, plant and equipment	13,400,000
Primoris AV
Nature of Business
Operating income							4,200,000
Revenue							$ 44,400,000