CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 5,276	$ 6,823
Restricted cash	312	603
Accounts receivable, net	3,794	3,271
Current portion of lease receivable	247	252
Costs and estimated earnings in excess of billings on uncompleted contracts	2,763	3,038
Inventories, net	3,973	3,751
Prepaid expenses and deposits	712	741
Total current assets	17,077	18,479
Long-term lease receivable, net of current portion	836	1,083
Property and equipment, net	4,527	4,638
Goodwill	635	635
Other assets	1,955	1,383
Total assets	25,030	26,218
Current liabilities:
Accounts payable	1,667	1,158
Accrued liabilities	912	1,400
Billings in excess of costs and estimated earnings on uncompleted contracts	4,574	6,500
Customer deposits	2,543	2,238
Current portion of retirement obligations	500	507
Current portion of pension settlement obligation	409	382
Current portion of long-term debt	224	211
Total current liabilities	10,829	12,396
Pension and retirement obligations, net of current portion	4,150	4,344
Pension settlement obligation, net of current portion	4,478	4,886
Long-term debt, net of current portion	1,540	1,764
Deferred rent obligation	808	1,231
Total liabilities	21,805	24,621
Stockholders' equity:
Preferred stock, no par value: 10,000,000 shares authorized; no shares outstanding	0	0
Common stock, $0.20 par value: 30,000,000 shares authorized; 11,616,866 shares issued	2,323	2,323
Additional paid-in-capital	53,818	53,641
Common stock in treasury, at cost, 264,350 shares	(3,532)	(3,532)
Accumulated deficit	(47,208)	(48,689)
Accumulated other comprehensive loss	(2,176)	(2,146)
Total stockholders' equity	3,225	1,597
Total liabilities and stockholders' equity	$ 25,030	$ 26,218