Cash, Cash Equivalents And Restricted Cash (Reconciliation Of Cash, Cash Equivalents And Restricted Cash) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016
Cash and cash equivalents	$ 118,258	$ 192,868
Restricted cash	3,436	4,780
Total cash, cash equivalents and restricted cash	121,694	197,648	$ 239,302	$ 196,607
Tutor Perini Corporation [Member]
Cash and cash equivalents	53,927	94,713
Joint Venture [Member]
Cash and cash equivalents	$ 64,331	$ 98,155

Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant