Contract Assets And Liabilities (Schedule Of Contract Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Contract Assets and Liabilities [Abstract]
Retainage receivable	$ 492,937	$ 535,939	$ 535,939
Claims	672,858	549,849
Unapproved change orders	349,286	296,591
Other unbilled costs and profits	63,507	86,318
Total costs and estimated earnings in excess of billings	1,085,651	932,758	$ 932,758
Capitalized contract costs	41,221	32,773
Total contract assets	$ 1,619,809	$ 1,501,470

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount billed to customers under long-term contracts or programs that have been withheld because of retainage provisions in a contract.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount of billed or unbilled claims or other similar items subject to uncertainty concerning their determination or ultimate realization under long-term contracts.

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Amount of cost incurred on construction contract for unapproved change order, claim, or similar item subject to uncertainty.

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Unbilled amounts due for 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 entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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