Other Comprehensive Income (Loss) (Schedule Of Changes In AOCI Balances By Component (After-Tax)) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Attributable to Tutor Perini Corporation:
Balance at the beginning of the period			$ 1,553,856
Other comprehensive income before reclassifications	$ 353	$ 2,136	(631)	$ 689
Amounts reclassified from AOCI	477	395	846	814
Total other comprehensive income	830	2,531	215	1,503
Balance at the end of the period	1,604,498		1,604,498
Defined Benefit Pension Plan
Attributable to Tutor Perini Corporation:
Balance at the beginning of the period	(43,595)	(37,403)	(44,087)	(37,826)
Other comprehensive income before reclassifications	0	0	0	0
Amounts reclassified from AOCI	491	424	983	847
Total other comprehensive income	491	424	983	847
Balance at the end of the period	(43,104)	(36,979)	(43,104)	(36,979)
Foreign Currency Translation
Attributable to Tutor Perini Corporation:
Balance at the beginning of the period	(5,246)	(7,364)	(5,322)	(5,371)
Other comprehensive income before reclassifications	120	801	196	(1,192)
Amounts reclassified from AOCI	0	0	0	0
Total other comprehensive income	120	801	196	(1,192)
Balance at the end of the period	(5,126)	(6,563)	(5,126)	(6,563)
Unrealized Gain (Loss) in Fair Value of Investments, Net
Attributable to Tutor Perini Corporation:
Balance at the beginning of the period	1,485	1,639	2,668	1,097
Other comprehensive income before reclassifications	233	1,335	(827)	1,881
Amounts reclassified from AOCI	(14)	(29)	(137)	(33)
Total other comprehensive income	219	1,306	(964)	1,848
Balance at the end of the period	1,704	2,945	1,704	2,945
Accumulated Other Comprehensive Income (Loss)
Attributable to Tutor Perini Corporation:
Balance at the beginning of the period	(47,356)	(43,128)	(46,741)	(42,100)
Balance at the end of the period	$ (46,526)	$ (40,597)	$ (46,526)	$ (40,597)