Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income tax provision (benefit)	$ 8,215	$ 19,067	$ 11,294	$ 30,421
Effective tax rate (as a percent)	41.10%	40.00%	40.10%	40.60%
Unrecognized tax benefits, including related interest and penalties			$ 7,900
Unrecognized tax benefits that would impact the effective tax rate	$ 6,800		6,800
Unrecognized tax benefits interest that would impact the effective tax rate	1,100		1,100
Tutor Perini Corporation [Member]
Income tax provision (benefit)	$ 3,008	$ (2,208)	$ (1,086)	$ (1,740)