Contract Receivables (Details) (USD $)	1 Months Ended	3 Months Ended
	Apr. 30, 2014	Mar. 31, 2014	Dec. 31, 2013
Contract Receivables [Abstract]
Maximum term of contract receivables (in months)		12 months
Components of contract receivables [Abstract]
Billed receivables		$ 6,789,000	$ 19,040,000
Recoverable costs and accrued profit not billed		7,737,000	5,519,000
Allowance for doubtful accounts		(2,000)	(2,000)
Total contract receivables, net		14,524,000	24,557,000
Unbilled Contract Receivables Billed during April 2014	$ 1,400,000
Contract Receivable [Member] | China Nuclear Power Engineering Company [Member]
Concentration Risk [Line Items]
Percentage of contract receivables accounted by major customers (in hundredths)		11.70%	4.90%
Contract Receivable [Member] | Slovenske elektrarne, a.s. [Member]
Concentration Risk [Line Items]
Percentage of contract receivables accounted by major customers (in hundredths)		9.90%	35.90%