Contract Receivables (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Retainages	$ 64,839	$ 133,619
Less allowances	0	0
Accounts receivable-trade, net	318,725	428,800
Contract Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Retainages	64,839	133,619
Unbilled	5,087	4,710
Less allowances	(22,531)	(22,116)
Accounts receivable-trade, net	318,725	428,800
Contract Receivable \| Contracts in progress
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contracts receivable	209,880	273,729
Contract Receivable \| Completed contracts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contracts receivable	$ 61,450	$ 38,858

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Amount billed to customers under long-term contracts or programs but not paid. Excludes amounts due that have been withheld because of retainage provisions in a contract.

+ References

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-Publisher FASB

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.3-4)

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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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- Definition

Amount billed to customers under long-term contracts or programs that have been withheld because of retainage provisions in a contract to be collected in the next fiscal year following the latest fiscal year.

+ References

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-Number 210

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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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-Publisher FASB

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