Contract Assets And Liabilities (Schedule Of Contract Liabilities) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Contract Assets and Liabilities [Abstract]
Retainage payable	$ 221,028	$ 211,956
Billings in excess of costs and estimated earnings	579,000	573,190
Total contract liabilities	$ 800,028	$ 785,146

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
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant