Business Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Reportable segment information
Revenues	$ 955,233	$ 992,928
(Loss) income from construction operations:
Income from construction operations	41,497	36,079
Total	3,525,349		3,397,438
Corporate
(Loss) income from construction operations:
Income from construction operations	(12,488)	(11,804)
Total	659,638		615,108
Operating segment
Reportable segment information
Revenues	979,852	1,058,335
(Loss) income from construction operations:
Income from construction operations	53,985	47,883
Total	2,865,711		2,782,330
Intersegment elimination
Reportable segment information
Revenues	(24,619)	(65,407)
Civil
Reportable segment information
Revenues	365,156	253,961
Civil | Operating segment
Reportable segment information
Revenues	376,392	305,249
(Loss) income from construction operations:
Income from construction operations	44,345	23,250
Total	1,456,420		1,384,937
Civil | Intersegment elimination
Reportable segment information
Revenues	(11,236)	(51,288)
Building
Reportable segment information
Revenues	297,932	437,100
Building | Operating segment
Reportable segment information
Revenues	311,315	451,209
(Loss) income from construction operations:
Income from construction operations	1,823	5,347
Total	656,775		663,314
Building | Intersegment elimination
Reportable segment information
Revenues	(13,383)	(14,109)
Specialty Contractors
Reportable segment information
Revenues	292,145	301,867
Specialty Contractors | Operating segment
Reportable segment information
Revenues	292,145	301,877
(Loss) income from construction operations:
Income from construction operations	7,817	19,286
Total	752,516		734,079
Specialty Contractors | Intersegment elimination
Reportable segment information
Revenues		$ (10)