Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Net (loss) income	$ (274)	$ 1,403
Adjustments to reconcile net income to operating cash flow:
Depreciation and amortization	2,633	2,305
Non-cash interest expense	9	0
Bad debt expense	50	0
Reserve for inventory obsolescence	580	320
Stock-based compensation	827	901
Deferred revenue	(72)	0
(Gain) loss on sale of property and equipment	(42)	39
(Increase) decrease in operating assets:
Accounts receivable	553	(814)
Inventories	280	(328)
Refundable income taxes	(612)	(462)
Prepaid expenses and other current assets	(291)	(231)
Increase (decrease) in operating liabilities:
Accounts payable	(586)	1,384
Accrued expenses	(588)	252
Accrued income taxes	(121)	(580)
Net cash provided by operating activities	2,346	4,189
Cash flows from investing activities:
Purchases of investments	(500)	(25)
Purchases of property and equipment	(2,581)	(3,932)
Proceeds from sale of property and equipment	90	37
Net cash used in investing activities	(2,991)	(3,920)
Cash flows from financing activities:
Borrowings under revolving credit facility	6,050	0
Payment of deferred financing costs	(69)	0
Purchase of treasury stock	(1,309)	(1,187)
Repayment of notes payable	(6,279)	(630)
Net cash used in financing activities	(1,607)	(1,817)
Net decrease in cash and cash equivalents	(2,252)	(1,548)
Cash and cash equivalents at the beginning of the period	4,978	8,812
Cash and cash equivalents at the end of the period	2,726	7,264
Supplemental cash flow information:
Cash paid for income taxes, net of refunds	724	2,098
Cash paid for interest	$ 189	$ 180