Contracts in Progress (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Contractors [Abstract]
Costs incurred on uncompleted contracts	$ 354,508	$ 750,218
Estimated earnings	70,731	171,475
Costs incurred and estimated earnings on uncompleted contracts	425,239	921,693
Less: Billings to date	(422,060)	(918,817)
Costs and estimated earnings in excess of billings on uncompleted contracts, net	3,179	2,876
Costs and estimated earnings in excess of billings on uncompleted contracts	20,363	19,245
Billings in excess of costs and estimated earnings on uncompleted contracts	$ (17,184)	$ (16,369)

Costs in Excess of Billings on Uncompleted Contracts, Net

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- Definition

Inventory for Long-term Contracts or Programs, Costs Incurred on Uncompleted Contracts

+ References

No definition available.

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- Definition

Inventory for Long-term Contracts or Programs, Estimated Earnings on Uncompleted Contracts

+ References

No definition available.

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- Definition

Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

+ References

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- Definition

Liability attributable to (i) billings in excess of costs under the percentage of completion contract accounting method representing the difference between contractually invoiced amounts (billings) and revenue recognized based, for example, on costs incurred to estimated total costs at period end or (ii) contractually invoiced amounts (billings) in excess of costs incurred and accumulated under the completed contract accounting method that are expected to be realized within one year or one operating cycle, whichever is longer, from the reporting date.

+ References

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Amount included in cost of uncompleted contracts in excess of related billings, or unbilled accounts receivable, which is expected to be collected within a year within one year (or one operating cycle, if longer) from the date of the balance sheet.

+ References

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Amount before progress payments and reserves of inventories associated with long-term contracts or programs.

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