Contracts in Progress and Advance Billings on Contracts - Components of Contracts in Progress and Advance Billings on Contracts (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Contractors [Abstract]
Costs incurred less costs of revenues recognized	$ 119,879	$ 112,819
Revenues recognized less billings to customers	238,622	323,010
Contracts in Progress	358,501	435,829
Billings to customers less revenues recognized	106,249	265,618
Costs incurred less costs of revenue recognized	32,023	(100,845)
Advance Billings on Contracts	$ 138,272	$ 164,773