Contract Assets And Liabilities (Schedule Of Contract Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Contract Assets and Liabilities [Abstract]
Retainage payable	$ 213,430	$ 261,820	$ 261,820
Billings in excess of costs and estimated earnings	648,287	496,654	$ 456,869
Total contract liabilities	$ 861,717	$ 758,474

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant