Costs and Estimated Earnings on Uncompleted Contracts - Schedule of Net Under (Over) Billings (Detail) $ in Thousands	Mar. 31, 2017 USD ($)
Contractors [Abstract]
Costs and estimated earnings in excess of billings on uncompleted contracts	$ 6,375
Billings in excess of costs and estimated earnings on uncompleted contracts	(3,701)
Net under (over) billings	$ 2,674

Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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