Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share [Abstract]
Net income attributable to Tutor Perini Corporation	$ 15,394	$ 36,819	$ 62,593	$ 72,899
Weighted-average common shares outstanding, basic (in shares)	51,072	50,787	50,995	50,598
Effect of dilutive restricted stock units and stock options (in shares)	294	454	369	406
Weighted-average common shares outstanding, diluted (in shares)	51,366	51,241	51,364	51,004
Net income attributable to Tutor Perini Corporation per common share: Basic (in dollars per share)	$ 0.30	$ 0.72	$ 1.23	$ 1.44
Net income attributable to Tutor Perini Corporation per common share: Diluted (in dollars per share)	$ 0.30	$ 0.72	$ 1.22	$ 1.43
Anti-dilutive securities not included above (in shares)	2,131	1,514	1,861	1,977