Separate Financial Information of Subsidiary Guarantors of Indebtedness (Condensed Consolidating Balance Sheet) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
ASSETS
Cash and Cash Equivalents	$ 170,744	$ 75,452	$ 96,894	$ 135,583
Restricted Cash	48,725	45,853
Accounts Receivable	1,718,685	1,473,615
Costs and Estimated Earnings in Excess of Billings	820,243	905,175
Deferred Income Taxes	26,029	26,306
Other Current Assets	65,511	108,844
Total current assets	2,849,937	2,635,245
Property and Equipment, net	492,328	523,525
Other Assets:
GOODWILL	585,006	585,006
Intangible Assets, net	93,883	96,540
OTHER ASSETS	199,812	196,361
TOTAL ASSETS	4,220,966	4,036,677
LIABILITIES AND STOCKHOLDERS' EQUITY
Current Maturities of Long-term Debt	108,897	88,917
Accounts Payable	949,648	937,464
Billings in Excess of Costs and Estimated Earnings	334,055	288,311
Accrued Expenses and Other Current Liabilities	209,343	159,016
Total current liabilities	1,601,943	1,473,708
Long-term Debt, less current maturities	684,202	728,767
Deferred Income Taxes	283,811	273,310
Other Long-term Liabilities	126,966	140,665
Contingencies and Commitments
Stockholders' Equity	1,524,044	1,420,227
TOTAL LIABILITIES AND STOCKHOLERS' EQUITY	4,220,966	4,036,677
Eliminations [Member]
ASSETS
Accounts Receivable	(219,804)	(146,745)
Costs and Estimated Earnings in Excess of Billings	(59,782)	(77,583)
Other Current Assets	(43,000)	(11,419)
Total current assets	(322,586)	(235,747)
Intercompany Notes and Receivables	(201,270)	(148,637)
Other Assets:
Investment in Subsidiaries	(2,173,219)	(1,962,983)
OTHER ASSETS	(5,926)	(5,723)
TOTAL ASSETS	(2,703,001)	(2,353,090)
LIABILITIES AND STOCKHOLDERS' EQUITY
Current Maturities of Long-term Debt	(60,000)	(60,000)
Accounts Payable	(202,002)	(167,705)
Billings in Excess of Costs and Estimated Earnings	(22,634)	(5,711)
Accrued Expenses and Other Current Liabilities	(37,950)	(2,331)
Total current liabilities	(322,586)	(235,747)
Long-term Debt, less current maturities	(5,926)	(5,723)
Intercompany Notes and Advances Payable	(201,270)	(148,637)
Contingencies and Commitments
Stockholders' Equity	(2,173,219)	(1,962,983)
TOTAL LIABILITIES AND STOCKHOLERS' EQUITY	(2,703,001)	(2,353,090)
Tutor Perini Corporation [Member]
ASSETS
Cash and Cash Equivalents	86,618	47,196	64,316	75,087
Restricted Cash	3,261	3,369
Accounts Receivable	407,677	358,437
Costs and Estimated Earnings in Excess of Billings	121,897	114,580
Deferred Income Taxes	16,323	2,255
Other Current Assets	58,268	60,119
Total current assets	694,044	585,956
Property and Equipment, net	85,639	105,306
Other Assets:
Investment in Subsidiaries	2,173,219	1,962,983
OTHER ASSETS	93,486	58,722
TOTAL ASSETS	3,046,388	2,712,967
LIABILITIES AND STOCKHOLDERS' EQUITY
Current Maturities of Long-term Debt	144,891	107,283
Accounts Payable	228,144	211,679
Billings in Excess of Costs and Estimated Earnings	105,501	89,303
Accrued Expenses and Other Current Liabilities	106,499	6,145
Total current liabilities	585,035	414,410
Long-term Debt, less current maturities	619,584	653,669
Deferred Income Taxes	49,645
Other Long-term Liabilities	106,106	106,588
Intercompany Notes and Advances Payable	161,974	118,073
Contingencies and Commitments
Stockholders' Equity	1,524,044	1,420,227
TOTAL LIABILITIES AND STOCKHOLERS' EQUITY	3,046,388	2,712,967
Guarantor Subsidiaries [Member]
ASSETS
Cash and Cash Equivalents	83,874	26,892	31,558	36,764
Restricted Cash	2,209	3,283
Accounts Receivable	1,414,817	1,179,919
Costs and Estimated Earnings in Excess of Billings	757,976	868,026
Deferred Income Taxes	9,706	21,356
Other Current Assets	39,635	48,482
Total current assets	2,308,217	2,147,958
Property and Equipment, net	402,823	414,143
Intercompany Notes and Receivables	201,270	148,637
Other Assets:
GOODWILL	585,006	585,006
Intangible Assets, net	93,883	96,540
OTHER ASSETS	86,517	128,094
TOTAL ASSETS	3,677,716	3,520,378
LIABILITIES AND STOCKHOLDERS' EQUITY
Current Maturities of Long-term Debt	24,006	41,634
Accounts Payable	921,046	890,268
Billings in Excess of Costs and Estimated Earnings	222,559	203,003
Accrued Expenses and Other Current Liabilities	92,474	115,392
Total current liabilities	1,260,085	1,250,297
Long-term Debt, less current maturities	70,544	80,821
Deferred Income Taxes	211,828	273,310
Other Long-term Liabilities	2,301	3,278
Contingencies and Commitments
Stockholders' Equity	2,132,958	1,912,672
TOTAL LIABILITIES AND STOCKHOLERS' EQUITY	3,677,716	3,520,378
Non-Guarantor Subsidiaries [Member]
ASSETS
Cash and Cash Equivalents	252	1,364	$ 1,020	$ 23,732
Restricted Cash	43,255	39,201
Accounts Receivable	115,995	82,004
Costs and Estimated Earnings in Excess of Billings	152	152
Deferred Income Taxes		2,695
Other Current Assets	10,608	11,662
Total current assets	170,262	137,078
Property and Equipment, net	3,866	4,076
Other Assets:
OTHER ASSETS	25,735	15,268
TOTAL ASSETS	199,863	156,422
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts Payable	2,460	3,222
Billings in Excess of Costs and Estimated Earnings	28,629	1,716
Accrued Expenses and Other Current Liabilities	48,320	39,810
Total current liabilities	79,409	44,748
Deferred Income Taxes	22,338
Other Long-term Liabilities	18,559	30,799
Intercompany Notes and Advances Payable	39,296	30,564
Contingencies and Commitments
Stockholders' Equity	40,261	50,311
TOTAL LIABILITIES AND STOCKHOLERS' EQUITY	$ 199,863	$ 156,422