Contract Receivables (Details) (USD $)	1 Months Ended	3 Months Ended
Oct. 31, 2014	Mar. 31, 2015	Dec. 31, 2014
Contract Receivables [Abstract]
Maximum term of contract receivables (in months)		12 months
Components of contract receivables [Abstract]
Billed receivables		$ 8,427,000us-gaap_BilledContractReceivables	$ 10,792,000us-gaap_BilledContractReceivables
Recoverable costs and accrued profit not billed		6,766,000us-gaap_UnbilledContractsReceivable	5,060,000us-gaap_UnbilledContractsReceivable
Allowance for doubtful accounts		2,000	22,000
Total contract receivables, net		15,191,000	15,830,000
Unbilled Contract Receivables Billed during April 2015	$ 2,300,000
State Nuclear Power Automation System Engineering Co. [Member]
Concentration Risk [Line Items]
Percentage of contract receivables accounted by major customers (in hundredths)		7.00%	10.20%

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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.

+ References

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- Definition

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

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

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- Definition

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

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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- 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.

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