Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities (net of net assets acquired):
Net loss	$ (5,812,000)	$ (3,870,000)	$ (6,370,000)
Adjustments to reconcile net loss to cash (used in) provided by operating activities:
Inventory reserve	321,000	313,000	205,000
Stock based compensation expense	2,163,000	2,437,000	1,658,000
Depreciation and amortization	1,561,000	1,132,000	685,000
Bad debt expense	31,000	115,000	117,000
Change in contingent consideration	169,000	94,000
Other non-cash items	85,000	(69,000)	2,000
Changes in:
Accounts receivable	(554,000)	1,597,000	1,174,000
Financing receivables	562,000	1,344,000	832,000
Inventory	(384,000)	87,000	3,027,000
Prepaid expenses and other assets	401,000	(138,000)	(1,120,000)
Deferred costs	(471,000)	1,790,000	(3,758,000)
Deferred revenue	(361,000)	186,000	2,939,000
Accounts payable and accrued expenses	587,000	(1,099,000)	(1,874,000)
Net cash (used in) provided by operating activities	(1,702,000)	3,919,000	(2,483,000)
Cash flows from investing activities:
Acquisition		(7,373,000)
Capital expenditures	(251,000)	(386,000)	(505,000)
Purchases of investments	(3,235,000)	(11,083,000)	(956,000)
Proceeds from the sale and maturities of investments	10,082,000	1,113,000	932,000
Net cash (used in) provided by investing activities	6,596,000	(17,729,000)	(529,000)
Cash flows from financing activities:
Net proceeds from underwritten public offering		16,065,000
Borrowings under revolving credit facility		11,655,000	14,650,000
Repayments under revolving credit facility		(14,648,000)	(11,657,000)
Proceeds from exercise of stock options	721,000	1,277,000	70,000
Common stock repurchased	(652,000)
Net cash provided by financing activities	69,000	14,349,000	3,063,000
Effect of foreign exchange rate changes on cash and cash equivalents	100,000	(413,000)	433,000
Net increase in cash, cash equivalents and restricted cash	5,063,000	126,000	484,000
Cash, cash equivalents and restricted cash - beginning of period	5,403,000	5,277,000	4,793,000
Cash, cash equivalents and restricted cash - end of period	10,466,000	5,403,000	5,277,000
Reconciliation of cash, cash equivalents, and restricted cash, beginning of period
Cash and cash equivalents	5,097,000	4,972,000	4,489,000
Restricted cash	306,000	305,000	304,000
Cash, cash equivalents, and restricted cash, beginning of period	5,403,000	5,277,000	4,793,000
Cash and cash equivalents	10,159,000	5,097,000	4,972,000
Restricted cash	307,000	306,000	305,000
Cash, cash equivalents, and restricted cash, end of period	10,466,000	5,403,000	5,277,000
Cash paid for:
Taxes
Interest		130,000	175,000
Non-cash investing and financing activities:
Unrealized (loss) gain on investments	66,000	(102,000)	(11,000)
Shares withheld pursuant to stock issuance	249,000	465,000	$ 323,000
Value of shares issued relating to acquisition contingent consideration	2,000,000
Value of shares issued pursuant to acquisition		2,000,000
Contingent consideration relating to acquisition		$ 2,683,000