Accounts Payable and Accrued Expenses - Summary of Accounts Payable and Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Trade accounts payable, including due to subcontractors	$ 65,668	$ 31,882
Compensation and related benefits	7,130	2,976
Accrued interest	107	193
Current portion of earn-out liability	14,377	8,738
Accrued warranty	3,220	936
Other accrued expenses	14,447	6,737
Accounts payable and accrued expenses	$ 104,949	$ 51,462