Other Comprehensive Income (Loss) (AOCI Reclassifications) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense)	$ (1,431)	$ 797	$ (1,606)	$ 316
Income tax expense (benefit)	10,635	9,576	17,599	14,710
Net income attributable to Tutor Perini Corporation	(31,165)	(18,709)	(47,199)	(36,080)
Defined Benefit Pension Plan | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense)	683	592	1,366	1,183
Income tax expense (benefit)	(192)	(168)	(383)	(336)
Net income attributable to Tutor Perini Corporation	491	424	983	847
Unrealized gain in fair value of investment adjustments | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense)	(17)	(37)	(173)	(42)
Income tax expense (benefit)	3	8	36	9
Net income attributable to Tutor Perini Corporation	$ (14)	$ (29)	$ (137)	$ (33)