Other Comprehensive Income (Loss) (Schedule of Tax Effects of the Components of Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Other Comprehensive Income (Loss) [Abstract]
Defined benefit pension plan adjustments, Before-Tax Amount	$ 464	$ 513	$ 1,390	$ 1,539
Defined benefit pension plan adjustments, Tax (Expense) Benefit	(133)	(148)	(398)	(439)
Defined benefit pension plan adjustments, Net-of-Tax Amount	331	365	992	1,100
Foreign currency translation adjustments, Before-Tax Amount	(590)	519	961	(2,034)
Foreign currency translation adjustments, Tax (Expense) Benefit	140	(143)	(253)	602
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total	(450)	376	708	(1,432)
Unrealized gain (loss) in fair value of investments, Before-Tax Amount	328	(173)	2,053	(1,468)
Unrealized gain (loss) in fair value of investments, Tax (Expense) Benefit	(72)	44	(438)	325
Unrealized gain (loss) in fair value of investments, Net-of-Tax Amount	256	(129)	1,615	(1,143)
Total other comprehensive income (loss), Before-Tax Amount	202	859	4,404	(1,963)
Total other comprehensive income (loss), Tax (Expense) Benefit	(65)	(247)	(1,089)	488
TOTAL OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	137	612	3,315	(1,475)
Less: Other comprehensive income (loss) attributable to noncontrolling interests, Before-of-Tax Amount	(99)	0	160	0
Less: Other comprehensive income (loss) attributable to noncontrolling interests, Tax (Expense) Benefit	0	0	0	0
Less: Other comprehensive income (loss) attributable to noncontrolling interests, Net-of-Tax Amount	(99)	0	160	0
Total other comprehensive income (loss) attributable to Tutor Perini Corporation, Before-Tax Amount	301	859	4,244	(1,963)
Total other comprehensive income (loss) attributable to Tutor Perini Corporation, Tax (Expense) Benefit	(65)	(247)	(1,089)	488
TOTAL OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	$ 236	$ 612	$ 3,155	$ (1,475)