Certain Balance Sheet Components Accounts Receivable, Net, Additional Information (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Current retainage contract receivables [Member]
Accounts Receivable, Net (Line Items]
Contract Receivable Retainage, Due One Year or Less	$ 3,100,000	$ 3,200,000
Unbilled Contracts Receivable	5,000,000	4,300,000
Long Term Retainage Contract Receivables [Member]
Accounts Receivable, Net (Line Items]
Long-term unbilled retainage receivables	4,500,000	4,700,000
Contract Receivable Retainage, Due after Next Rolling Twelve Months	$ 0	$ 0

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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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- 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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Period Type:	instant

- 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 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 2: 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 3: 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

- 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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