Costs And Estimated Earnings On Uncompleted Contracts (Costs And Estimated Earnings On Uncompleted Contracts Accompanying Consolidated Balance Sheets) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Costs And Estimated Earnings On Uncompleted Contracts [Abstract]
Costs and estimated earnings in excess of billings on uncompleted contracts	$ 12,508	$ 11,127
Billings in excess of costs and estimated earnings on uncompleted contracts (included in Other current liabilities)	(269)	(1,392)
Costs and estimated earnings on uncompleted contracts	$ 12,239	$ 9,735