Summary of Contract Receivables (Detail) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Retainages	$ 43,370	$ 63,558
Unbilled	1,346	12,697
Less allowances	(16,683)	(29,561)
Accounts receivable-trade, net	296,303	323,497
Contracts in progress
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contract receivables	241,917	191,216
Completed contracts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contract receivables	$ 26,353	$ 85,587

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Schedule amount of the billed retainage expected to be collected within one year from the balance sheet date.

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Amounts due for 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 entity and, at a minimum, one other party. Such amounts may be billed or unbilled depending on the specifics of the contract.

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- Definition

The amount by which the estimate of total contract revenue is exceeded by the estimate of total contract costs. May also include anticipated contract penalties.

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Unbilled amounts due for 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 entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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