Revenue Recognition - Additional Information (Detail)		3 Months Ended		9 Months Ended		12 Months Ended
		Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) Project	Sep. 30, 2015 USD ($)	Dec. 31, 2015 Project
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Unapproved change orders		$ 139,000,000	$ 146,000,000	$ 139,000,000	$ 146,000,000
Revenues	[1]	558,543,000	805,857,000	1,994,202,000	2,402,857,000
Cost of operations		455,499,000	720,961,000	1,666,974,000	2,121,942,000
MEA [Member] | Unconsolidated joint ventures [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Revenues		0	0
Cost of operations		0	0
MEA [Member] | Claims Revenue [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Revenues				16,000,000	10,000,000
Cost of operations				16,000,000	10,000,000
Backlog [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Unapproved change orders		$ 21,000,000	$ 23,000,000	$ 21,000,000	$ 23,000,000
Active Projects [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Number of projects accounted under deferred profit recognition policy | Project				0		0

[1] Intersegment transactions included in revenues were not significant for either of the periods presented.