Separate Financial Information of Subsidiary Guarantors of Indebtedness, Condensed Consolidating Balance Sheet (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
CONDENSED CONSOLIDATING BALANCE SHEET
Ownership interest in guarantors	100.00%
ASSETS
Cash and Cash Equivalents	$ 96,894	$ 135,583	$ 137,228	$ 119,923
Restricted Cash	38,572	44,370
Accounts Receivable	1,550,865	1,479,504
Costs and Estimated Earnings in Excess of Billings	883,809	726,402
Deferred Income Taxes	18,873	17,962
Other Current Assets	86,734	68,735
Total current assets	2,675,747	2,472,556
Property and Equipment, net	531,438	527,602
Other Assets:
Goodwill	585,006	585,006
Intangible Assets, net	97,425	100,254
Other	80,639	87,897
Total assets	3,970,255	3,773,315
LIABILITIES AND STOCKHOLDERS' EQUITY
Current Maturities of Long-term Debt	85,897	81,292
Accounts Payable	985,217	798,174
Billings in Excess of Costs and Estimated Earnings	286,565	319,296
Accrued Expenses and Other Current Liabilities	185,764	159,814
Total current liabilities	1,543,443	1,358,576
Long-term Debt, less current maturities	746,283	784,067
Deferred Income Taxes	149,021	150,371
Other Long-term Liabilities	$ 114,902	$ 114,796
Contingencies and Commitments
Stockholders' Equity	$ 1,416,606	$ 1,365,505
Total liabilities and stockholders' equity	3,970,255	3,773,315
Eliminations [Member]
ASSETS
Accounts Receivable	(121,181)	(103,622)
Costs and Estimated Earnings in Excess of Billings	(76,495)	(44,456)
Deferred Income Taxes		2,323
Other Current Assets	(78,615)	(37,608)
Total current assets	(276,291)	(183,363)
Intercompany Notes and Receivables	(186,736)	(122,401)
Other Assets:
Investment in Subsidiaries	(1,998,039)	(2,174,131)
Other	(5,655)	(5,453)
Total assets	(2,466,721)	(2,485,348)
LIABILITIES AND STOCKHOLDERS' EQUITY
Current Maturities of Long-term Debt	(41,000)
Accounts Payable	(187,314)	(109,384)
Billings in Excess of Costs and Estimated Earnings	(2,239)	(8,203)
Accrued Expenses and Other Current Liabilities	(45,738)	(26,952)
Total current liabilities	(276,291)	(144,539)
Long-term Debt, less current maturities	(5,655)	(40,453)
Intercompany Notes and Advances Payable	$ (186,736)	$ (125,992)
Contingencies and Commitments
Stockholders' Equity	$ (1,998,039)	$ (2,174,363)
Total liabilities and stockholders' equity	(2,466,721)	(2,485,347)
Tutor Perini Corporation [Member]
ASSETS
Cash and Cash Equivalents	64,316	75,087	70,445	88,995
Restricted Cash	3,369	3,369
Accounts Receivable	427,119	299,427
Costs and Estimated Earnings in Excess of Billings	110,378	70,344
Deferred Income Taxes	4,787
Other Current Assets	76,162	39,196
Total current assets	686,131	487,423
Property and Equipment, net	107,030	92,413
Other Assets:
Investment in Subsidiaries	1,998,039	2,154,562
Other	57,170	83,503
Total assets	2,848,370	2,817,901
LIABILITIES AND STOCKHOLDERS' EQUITY
Current Maturities of Long-term Debt	81,825	34,776
Accounts Payable	250,379	186,958
Billings in Excess of Costs and Estimated Earnings	100,598	139,020
Accrued Expenses and Other Current Liabilities	50,226	33,018
Total current liabilities	483,028	393,772
Long-term Debt, less current maturities	664,931	712,460
Deferred Income Taxes		142,457
Other Long-term Liabilities	112,909	112,899
Intercompany Notes and Advances Payable	$ 152,120	$ 90,373
Contingencies and Commitments
Stockholders' Equity	$ 1,435,382	$ 1,365,939
Total liabilities and stockholders' equity	2,848,370	2,817,900
Guarantor Subsidiaries [Member]
ASSETS
Cash and Cash Equivalents	31,558	36,764	58,914	18,031
Restricted Cash	4,008	5,274
Accounts Receivable	1,186,601	1,246,635
Costs and Estimated Earnings in Excess of Billings	849,774	700,362
Deferred Income Taxes	12,955	15,639
Other Current Assets	51,422	42,750
Total current assets	2,136,318	2,047,424
Property and Equipment, net	420,262	430,876
Intercompany Notes and Receivables	186,736	122,401
Other Assets:
Goodwill	585,006	585,006
Intangible Assets, net	97,425	100,254
Investment in Subsidiaries		19,519
Other	27,363	9,847
Total assets	3,453,110	3,315,327
LIABILITIES AND STOCKHOLDERS' EQUITY
Current Maturities of Long-term Debt	45,072	46,516
Accounts Payable	918,808	716,851
Billings in Excess of Costs and Estimated Earnings	188,172	185,807
Accrued Expenses and Other Current Liabilities	118,252	95,177
Total current liabilities	1,270,304	1,044,351
Long-term Debt, less current maturities	87,007	112,060
Deferred Income Taxes	149,021	7,914
Other Long-term Liabilities	$ 1,993	$ 1,897
Contingencies and Commitments
Stockholders' Equity	$ 1,944,785	$ 2,149,105
Total liabilities and stockholders' equity	3,453,110	3,315,327
Non-Guarantor Subsidiaries [Member]
ASSETS
Cash and Cash Equivalents	1,020	23,732	$ 7,869	$ 12,897
Restricted Cash	31,195	35,727
Accounts Receivable	58,326	37,064
Costs and Estimated Earnings in Excess of Billings	152	152
Deferred Income Taxes	1,131
Other Current Assets	37,765	24,397
Total current assets	129,589	121,072
Property and Equipment, net	4,146	4,313
Other Assets:
Investment in Subsidiaries		50
Other	1,761
Total assets	135,496	125,435
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts Payable	3,344	3,749
Billings in Excess of Costs and Estimated Earnings	34	2,672
Accrued Expenses and Other Current Liabilities	63,024	58,571
Total current liabilities	66,402	64,992
Intercompany Notes and Advances Payable	$ 34,616	$ 35,619
Contingencies and Commitments
Stockholders' Equity	$ 34,478	$ 24,824
Total liabilities and stockholders' equity	$ 135,496	$ 125,435
Senior Unsecured Notes [Member]
CONDENSED CONSOLIDATING BALANCE SHEET
Interest rate	7.625%