Fair Value Measurements (Schedule of Financial Statement Items Carried at Estimated Fair Value) (Details) - USD ($)	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014	Jun. 05, 2014
Assets:
Restricted cash	$ 38,572,000	$ 44,370,000
Tutor Perini Corporation [Member]
Assets:
Restricted cash	3,369,000	3,369,000
Fair Value Measured On A Recurring Basis [Member] | Quoted prices in active markets (Level 1) [Member]
Assets:
Cash and cash equivalents	96,894,000	135,583,000
Restricted cash	38,572,000	44,370,000
Investments in lieu of retainage	30,973,000	25,761,000
Total assets	166,439,000	205,714,000
Fair Value Measured On A Recurring Basis [Member] | Significant other observable inputs (Level 2) [Member]
Assets:
Investments in lieu of retainage	6,644,000	7,463,000
Total assets	6,644,000	7,463,000
Liabilities:
Interest rate swap contract	130,000	381,000
Total liabilities	130,000	381,000
Fair Value Measured On A Recurring Basis [Member] | Significant unobservable inputs (Level 3) [Member]
Liabilities:
Contingent consideration	26,181,000	24,814,000
Total liabilities	26,181,000	24,814,000
Carrying Value [Member] | Fair Value Measured On A Recurring Basis [Member]
Assets:
Cash and cash equivalents	96,894,000	135,583,000
Restricted cash	38,572,000	44,370,000
Investments in lieu of retainage	37,617,000	33,224,000
Total assets	173,083,000	213,177,000
Liabilities:
Interest rate swap contract	130,000	381,000
Contingent consideration	26,181,000	24,814,000
Total liabilities	26,311,000	$ 25,195,000
Term Loan [Member]
Liabilities:
Face amount	$ 250,000,000		$ 200,000,000
Term of debt	5 years
Issuance date	Jun. 05, 2014
Maturity date	Jun. 05, 2019