Summary Of Major Accounting Policies - Percentage-of-Completion (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule Temporary Differences Using Percentage of Completion [Line Items]
Revenue Recognition, Multiple-deliverable Arrangements, Percentage of Revenue Accounted Under the Percentage of Completion Method	16.00%
Contract in Unbilled Receivable Position [Member]
Schedule Temporary Differences Using Percentage of Completion [Line Items]
Fixed-price Contract, Percentage of Completion, Revenue Recognized to Date	$ 694,690	$ 368,888
Billed Contracts Receivable	(649,550)	(312,968)
Costs in Excess of Billings on Uncompleted Contracts or Programs	45,140	55,920
Contracts in Unearned Revenue Position [Member]
Schedule Temporary Differences Using Percentage of Completion [Line Items]
Fixed-price Contract, Percentage of Completion, Revenue Recognized to Date	(190,812)	(109,547)
Billed Contracts Receivable	302,904	196,501
Billings in Excess of Cost	$ 112,092	$ 86,954

Fixed-price Contract, Percentage of Completion, Revenue Recognized to Date

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Revenue Recognition, Multiple-deliverable Arrangements, Percentage of Revenue Accounted Under the Percentage of Completion Method

+ References

No definition available.

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Schedule Temporary Differences Using Percentage of Completion [Line Items]

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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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 3
-Article 5

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 35
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6802688&loc=d3e57807-111642

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Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
-SubTopic 310
-Section 45
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Regulation S-X (SX)
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