Other Comprehensive Income (Loss) (Schedule Of Components Of Other Comprehensive Income (Loss) And Related Tax Effects) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Defined benefit pension plan adjustments, Before-Tax Amount	$ 683	$ 592	$ 2,049	$ 1,775
Defined benefit pension plan adjustments, Tax (Expense) Benefit	(191)	(168)	(574)	(504)
Defined benefit pension plan adjustments, Net-of-Tax Amount	(492)	(424)	(1,475)	(1,271)
Foreign currency translation adjustment, Before-Tax Amount	(1,389)	1,333	(541)	(1,621)
Foreign currency translation adjustment, Tax (Expense) Benefit	264	(231)	188	365
Foreign currency translation adjustment, Net-of-Tax Amount	(1,125)	1,102	(353)	(1,256)
Unrealized gain (loss) in fair value of investments, Before-Tax Amount	(581)	(281)	(1,828)	2,078
Unrealized gain (loss) in fair value of investments, Tax (Expense) Benefit	133	56	416	(455)
Unrealized gain (loss) in fair value of investments, Net-of-Tax Amount	(448)	(225)	(1,412)	1,623
Total other comprehensive income (loss), Before-Tax Amount	(1,287)	1,644	(320)	2,232
Total other comprehensive income (loss), Tax Benefit (Expense)	206	(343)	30	(594)
TOTAL OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	(1,081)	1,301	(290)	1,638
Less: Other comprehensive income (loss) attributable to noncontrolling interests, Before-Tax Amount	(447)	520	129	(646)
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	(447)	520	129	(646)
Total other comprehensive income (loss) attributable to Tutor Perini Corporation, Before-Tax Amount	(840)	1,124	(449)	2,878
Total other comprehensive income (loss) attributable to Tutor Perini Corporation, Tax (Expense) Benefit	206	(343)	30	(594)
Total other comprehensive income (loss)	$ (634)	$ 781	$ (419)	$ 2,284