Revenue (Summary of Gross Profit from Foreign Operations) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation Of Revenue [Line Items]
CONTRACT REVENUES	$ 620,795	$ 592,159	$ 637,468
Costs of contract revenues	(509,335)	(549,429)	(552,130)
GROSS PROFIT	111,460	42,730	85,338
Foreign [Member]
Disaggregation Of Revenue [Line Items]
CONTRACT REVENUES	14,088	42,306	59,413
Costs of contract revenues	(19,866)	(73,958)	(66,729)
GROSS PROFIT	$ (5,778)	$ (31,652)	$ (7,316)

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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