Construction Contracts in Progress - Summary of Contracts in Progress (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Summary of Contracts in Progress [Abstract]
Costs incurred on uncompleted contracts	$ 111,925	$ 94,686
Estimated earnings	55,527	52,246
Earned revenue	167,452	146,932
Less billings to date	(162,427)	(141,478)
Total	5,025	5,454
Classified as follows:
Costs and estimated earnings in excess of billings on uncompleted contracts	6,755	7,312
Billings in excess of costs and estimated earnings on uncompleted contracts	$ (1,730)	$ (1,858)