Fabrication Contracts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Costs, estimated earnings and billings on uncompleted contracts
Costs incurred on uncompleted contracts	$ 895,337	$ 1,318,971
Estimated earnings	157,893	277,768
Total cost incurred and estimated earnings on uncompleted contracts	1,053,230	1,596,739
Less - billings to date	(1,014,977)	(1,579,448)
Total	$ 38,253	$ 17,291

Billings to date on uncompleted percentage of completion contracts.

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Total cost incurred and estimated earnings on uncompleted percentage-of-completion projects.

No definition available.

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Total costs and estimated earnings on uncompleted contracts net of billings to date

No definition available.

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Cost incurred on uncompleted percentage of completion projects.

No definition available.

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Estimated earnings on uncompleted percentage of completion projects.

No definition available.

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