Certain Balance Sheet Components Accounts Receivable, Net, Additional Information (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Current retainage contract receivables [Member]
Accounts Receivable, Net (Line Items]
Contract Receivable Retainage, Next Rolling Twelve Months	$ 4,700,000	$ 3,200,000
Unbilled Contracts Receivable	3,600,000	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

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.

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

Name:	us-gaap_UnbilledContractsReceivable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant