Costs And Estimated Earnings On Uncompleted Contracts (Summary Of Costs And Estimated Earnings On Uncompleted Contracts) (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Contracts In Progress Costs And Earnings [Line Items]
Costs and estimated earnings on uncompleted contracts	$ 18,940	$ 17,352
Cost incurred on uncompleted contracts [Member]
Contracts In Progress Costs And Earnings [Line Items]
Costs and estimated earnings on uncompleted contracts	48,749	37,790
Estimated earnings [Member]
Contracts In Progress Costs And Earnings [Line Items]
Costs and estimated earnings on uncompleted contracts	17,919	14,268
Billings to date [Member]
Contracts In Progress Costs And Earnings [Line Items]
Costs and estimated earnings on uncompleted contracts	$ (47,728)	$ (34,706)