Contracts in Progress and Advance Billings on Contracts - Components of Contracts in Progress and Advance Billings on Contracts (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Contractors [Abstract]
Costs incurred less costs of revenue recognized	$ 93,047	$ 112,819
Revenues recognized less billings to customers	211,743	323,010
Contracts in Progress	304,790	435,829
Billings to customers less revenue recognized	30,484	265,618
Costs incurred less costs of revenue recognized	70,937	(100,845)
Advance Billings on Contracts	$ 101,421	$ 164,773