Contracts in Progress and Advance Billings on Contracts - Components of Contracts in Progress and Advance Billings on Contracts (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Contractors [Abstract]
Costs incurred less costs of revenue recognized	$ 112,819	$ 90,191
Revenues recognized less billings to customers	323,010	267,426
Contracts in Progress	435,829	357,617
Billings to customers less revenue recognized	265,618	578,896
Costs incurred less costs of revenue recognized	(100,845)	(379,031)
Advance Billings on Contracts	$ 164,773	$ 199,865