Contracts in Progress (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Contractors [Abstract]
Costs incurred on uncompleted contracts	$ 668,848	$ 802,140
Estimated earnings	120,751	143,975
Costs incurred and estimated earnings on uncompleted contracts	789,599	946,115
Less: Billings to date	(777,516)	(933,828)
Costs and estimated earnings in excess of billings on uncompleted contracts, net	12,083	12,287
Costs and estimated earnings in excess of billings on uncompleted contracts	46,006	39,968
Billings in excess of costs and estimated earnings on uncompleted contracts	$ (33,923)	$ (27,681)

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

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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 FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-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
-SubTopic 35
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=68068069&loc=d3e57788-111642

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=68068069&loc=d3e57795-111642

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-Publisher FASB
-Name Accounting Standards Codification
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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

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