Contracts in Progress (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Contractors [Abstract]
Costs incurred on uncompleted contracts	$ 554,109	$ 360,678
Estimated earnings	97,687	47,208
Costs incurred and estimated earnings on uncompleted contracts	651,796	407,886
Less: Billings to date	(623,919)us-gaap_BilledContractReceivables	(397,625)us-gaap_BilledContractReceivables
Costs and estimated earnings in excess of billings on uncompleted contracts, net	27,877	10,261
Costs and estimated earnings in excess of billings on uncompleted contracts	44,581	24,856
Billings in excess of costs and estimated earnings on uncompleted contracts	$ (16,704)us-gaap_BillingsInExcessOfCostCurrent	$ (14,595)us-gaap_BillingsInExcessOfCostCurrent

Costs in Excess of Billings on Uncompleted Contracts, Net

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- Definition

Inventory for Long-term Contracts or Programs, Costs Incurred on Uncompleted Contracts

+ References

No definition available.

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- Definition

Inventory for Long-term Contracts or Programs, Estimated Earnings on Uncompleted Contracts

+ References

No definition available.

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- Definition

Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

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-Publisher FASB

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-Topic 210

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-Subparagraph (SX 210.5-02.3(c))

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- Definition

Liability attributable to (i) billings in excess of costs under the percentage of completion contract accounting method representing the difference between contractually invoiced amounts (billings) and revenue recognized based, for example, on costs incurred to estimated total costs at period end or (ii) contractually invoiced amounts (billings) in excess of costs incurred and accumulated under the completed contract accounting method that are expected to be realized within one year or one operating cycle, whichever is longer, from the reporting date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

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- Definition

Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings which is expected to be collected within one year or the normal operating cycle, if longer.

+ References

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- Definition

Amount before valuation and LIFO reserves, and progress payments, of inventory associated with long-term contracts, expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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

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-Number 210

-Section 02

-Paragraph 6

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