Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities:
Net income	$ 3,479	$ 1,972
Adjustments to reconcile net income to operating cash flow:
Depreciation and amortization	3,020	3,129
Loss on sale of investments, net	15	72
Impairment of investments	0	475
Deferred income taxes	(531)	(585)
Bad Debt expense	0	73
Reserve for inventory obsolescence	200	0
Stock-based compensation	326	0
(Gain) Loss on sale of equipment	284	(253)
(Increase) decrease in operating assets:
Accounts receivable	292	507
Inventories	(579)	(1,849)
Refundable income taxes	140	691
Prepaid expenses and other current assets	(584)	184
Increase (decrease) in operating liabilities:
Accounts payable	(2,673)	2,229
Accrued expenses	599	48
Income taxes payable	1,116	52
Net cash provided by operating activities	5,104	6,745
Cash flows from investing activities:
Purchases of investments	(559)	(1,489)
Proceeds from sale of investments	2,751	1,714
Redemption of certificates of deposit	513	272
Investments in certificates of deposits	0	(635)
Purchases of property and equipment	(3,237)	(1,995)
Proceeds from sale of equipment	172	353
Net cash used in investing activities	(360)	(1,780)
Cash flows from financing activities:
Purchase of treasury stock	(738)	(1,542)
Repayment of notes payable	(840)	(1,037)
Net cash used in financing activities	(1,578)	(2,579)
Net increase in cash and cash equivalents	3,166	2,386
Cash and cash equivalents at the beginning of the period	5,646	3,260
Cash and cash equivalents at the end of the period	8,812	5,646
Supplemental cash flow information:
Cash paid for income taxes, net of refunds	1,421	1,920
Cash paid for interest	$ 220	$ 235