Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Operating activities:
Net loss	$ (606)	$ (429)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	184	187
Stock compensation expense	47	57
Changes in assets and liabilities related to operations:
Trade accounts receivable	(871)	(1,078)
Other accounts receivable		1
Inventories	124	45
Prepaid expenses and other assets	15	(48)
Accounts payable	525	264
Accrued expenses	(30)	(67)
Net cash used in operating activities	(612)	(1,068)
Investing activities:
Acquisition of equipment and leasehold improvements	(38)	(30)
Payment of accounts payable incurred for the purchase of equipment and leasehold improvements	(8)	(23)
Net cash used in investing activities	(46)	(53)
Financing activities:
Principal payments on capital leases	(23)	(7)
Proceeds from exercise of stock options	26	0
Net cash provided by (used in) financing activities	3	(7)
Decrease in cash and cash equivalents	(655)	(1,128)
Cash and cash equivalents at beginning of period	1,862	3,276
Cash and cash equivalents at end of period	1,207	2,148
Supplemental cash flow information:
Interest paid	3	1
Supplemental non-cash investing and financing activities:
Accounts payable incurred for the purchase of equipment and leasehold improvements	$ 61	$ 10