Contract Receivables (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jan. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Contract Receivables [Abstract]
Maximum term of contract receivables		12 months
Components of contract receivables [Abstract]
Billed receivables				$ 8,154,000	$ 13,325,000
Recoverable costs and accrued profit not yet billed				5,980,000	5,555,000
Allowance for doubtful accounts	$ (137,000)	$ (137,000)	$ (17,000)	(137,000)	(17,000)
Total contract receivables, net				13,997,000	$ 18,863,000
Allowance for Doubtful Accounts Receivable [Roll Forward]
Allowance for Doubtful Accounts Receivable	137,000	17,000	103,000
Provision for Doubtful Accounts		118,000	0
Allowance for Doubtful Accounts Receivable, Write-offs		0	(86,000)
Currency Adjustments for Allowance for Doubtful Accounts		2,000	0
Allowance for Doubtful Accounts Receivable, Ending Balance		$ 137,000	$ 17,000
Subsequent Billing	$ 4,700,000
Net exposure to Westinghouse				$ 31,000