Costs And Estimated Earnings In Excess Of Billings On Uncompleted Contracts (Narrative) (Details)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Costs And Estimated Earnings In Excess Of Billings On Uncompleted Contracts [Abstract]
Costs and estimated earnings in excess of billings on uncompleted contracts, net of billings in excess of costs and estimated earnings	91.40%	81.40%
Number of significant customers	5	5

Costs And Estimated Earnings In Excess Of Billings On Uncompleted Contracts Net

No definition available.

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Balance Type:	na
Period Type:	duration