Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Operating activities
Net (loss) income	$ (1,268)	$ 513
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities:
Inventories allowances	33	43
Deferred tax expense	(121)	255
Depreciation and amortization	229	214
Share-based compensation expense	2	12
Loss on disposal of property, plant and equipment	104	0
Changes in operating assets and liabilities:
Trade accounts receivable	160	(3,127)
Inventories	(785)	(785)
Prepaid expenses and other current assets	368	(64)
Other assets	(5)	9
Accounts payable	673	1,860
Accrued compensation and related taxes	(912)	199
Accrued warranty expense	196	(20)
Deferred revenue	(24)	(24)
Customer deposits	0	3,507
Accrued other expenses and other current liabilities	233	20
Net cash (used in) provided by operating activities	(1,117)	2,612
Investing activities
Purchases of property, plant and equipment	(319)	(455)
Investment in securities	0	(481)
Net cash used in investing activities	(319)	(936)
Financing activities
Proceeds from issuance of common stock	183	0
Cash dividends declared and paid	(1,235)	0
Repurchase of common stock	(97)	0
Cash provided by financing activities	(1,149)	0
Net change in cash and cash equivalents	(2,585)	1,676
Cash and cash equivalents, beginning of period	10,910	4,669
Cash and cash equivalents, end of period	8,325	6,345
Supplemental disclosure
Cash paid for interest	0	0
Income tax paid	0	0
Non-cash financing activity
Cashless exercise of stock options and related conversion of net shares to stockholders' equity	$ 27	$ 0