Summary of Contract Receivables (Detail) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Retainages	$ 38,286	$ 63,558
Unbilled	250	12,697
Less allowances	(30,897)	(29,561)
Accounts receivable-trade, net	357,242	323,497
Contracts in progress
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contract receivables	227,816	191,216
Completed contracts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contract receivables	$ 121,787	$ 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.

+ References

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- Definition

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

+ References

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- Definition

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.

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
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-Paragraph 89
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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.

+ References

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