Contract Receivables (Details) - USD ($) $ in Thousands	1 Months Ended	6 Months Ended
Jul. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Contract Receivables [Abstract]
Maximum term of contract receivables (in months)		12 months
Components of contract receivables [Abstract]
Billed receivables		$ 10,410	$ 10,792
Recoverable costs and accrued profit not billed		5,554	5,060
Allowance for doubtful accounts		2	22
Total contract receivables, net		$ 15,962	$ 15,830
Unbilled Contract Receivables Billed during July 2015	$ 2,200
State Nuclear Power Automation System Engineering Co. [Member]
Concentration Risk [Line Items]
Percentage of contract receivables accounted by major customers (in hundredths)		5.80%	10.20%
China Nuclear Power Engineering Company [Member]
Concentration Risk [Line Items]
Percentage of contract receivables accounted by major customers (in hundredths)		15.20%	3.90%

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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No definition available.

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Describes the maximum period under which the entity considered its contract receivables to be collected.

+ References

No definition available.

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- Definition

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

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

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- Definition

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

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Amounts due for billed 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 Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

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- Definition

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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The increase (decrease) during the reporting period of the amount of revenue for work performed for which billing has not occurred, net of uncollectible accounts.

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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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