v2.4.0.6

Certain Balance Sheet Components Accounts Receivable, Net, Additional Information (Details) (USD $) | Mar. 31, 2013 | Dec. 31, 2012
--- | --- | ---
Accounts Receivable, Net (Line Items] |  |
Contract Receivable Retainage, Due after Next Rolling Twelve Months | $ 0 | $ 0
Number of months current retainage amounts and unbilled receivables are expected to be collected | 12 months |
Current retainage contract receivables [Member] |  |
Accounts Receivable, Net (Line Items] |  |
Contract Receivable Retainage, Due One Year or Less | 19,500,000 | 20,000,000
Unbilled Contracts Receivable | 7,600,000 | 11,100,000
Long Term Retainage Contract Receivables [Member] |  |
Accounts Receivable, Net (Line Items] |  |
Long-term unbilled retainage receivables | $ 2,500,000 | $ 0

X
- Definition The number of months within which current retainage amounts and unbilled receivables are expected to be collected, as of the balance sheet date. + References No definition available. + Details
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Balance Type: | na
Period Type: | instant

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- Details
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Balance Type: | na
Period Type: | duration

X
- 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 after the next rolling twelve months following the latest balance sheet presented. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 3 -Subparagraph c -Article 5 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Section A -Paragraph 4, 21 -Chapter 11 -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. Reference 2: 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(c)(3)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 3 -Subparagraph c(3) -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 912 -SubTopic 310 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6471842&loc=d3e55302-109406 + Details
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Balance Type: | debit
Period Type: | instant

X
- Definition Amount of unbilled receivables under long-term contracts that have not been billed and were not billable that are expected to be collected after the next fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 910 -SubTopic 310 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6471494&loc=d3e49336-109356 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant