Costs And Estimated Earnings In Excess Of Billings On Uncompleted Contracts (Summary Of Cost And Estimated Earnings On Uncompleted Contracts) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Contracts In Progress Costs And Earnings [Line Items]
Costs and estimated earnings on uncompleted contracts	$ 17,352	$ 16,767
Cost Incurred On Uncompleted Contracts [Member]
Contracts In Progress Costs And Earnings [Line Items]
Costs and estimated earnings on uncompleted contracts	37,790	43,686
Estimated Earnings [Member]
Contracts In Progress Costs And Earnings [Line Items]
Costs and estimated earnings on uncompleted contracts	14,268	14,809
Billings To Date [Member]
Contracts In Progress Costs And Earnings [Line Items]
Costs and estimated earnings on uncompleted contracts	$ (34,706)	$ (41,728)