Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Operating activities
Net income	$ 513	$ 538
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Inventories reserve	43	25
Deferred tax expense	255	205
Depreciation and amortization	214	218
Share-based compensation expense	12	7
Changes in operating assets and liabilities:
Accounts receivable	(3,127)	(2,481)
Inventories	(785)	537
Prepaid expenses and other current assets	(64)	241
Other assets	9	14
Accounts payable	1,860	103
Accrued compensation and related taxes	199	39
Accrued warranty expense	(20)	30
Deferred revenue	(24)	(19)
Customer deposits	3,507	0
Accrued other expenses and other current liabilities	20	(74)
Net cash provided by (used in) operating activities	2,612	(617)
Investing activities
Purchases of property, plant and equipment	(455)	(102)
Investment in securities	(481)	0
Net cash used in investing activities	(936)	(102)
Financing activities
Proceeds from issuance of common stock	0	41
Cash provided by financing activities	0	41
Net change in cash and cash equivalents	1,676	(678)
Cash and cash equivalents, beginning of period	4,669	11,363
Cash and cash equivalents, end of period	6,345	10,685
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	$ 0	$ 6