Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Operating Activities
Net income (loss)	$ 298	$ (2,735)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation	457	495
Amortization	114	139
Loss (gain) on sale of equipment	13	(3)
Provision for doubtful accounts, net of recoveries	(2)	(1,144)
Stock-based compensation, net of forfeitures	61	208
Changes in operating assets and liabilities:
Accounts receivable	1,405	(863)
Inventories	(32)	(71)
Prepaid expenses, other current assets and other non-current assets	1,176	239
Accounts payable	(980)	820
Accrued liabilities and other non-current liabilities	(382)	(376)
Net cash provided by (used in) operating activities	572	(3,291)
Investing Activities
Purchases of equipment and patents	(584)	(206)
Net cash used in investing activities	(584)	(206)
Financing Activities
Proceeds from sale of common stock issued in connection with private placement	25,812	0
Costs related to sale of common stock issued in connection with private placement	(1,783)	0
Taxes paid on behalf of equity award participants	(52)	(6)
Net cash provided by financing activities	23,977	1,550
Effect of exchange rate fluctuations on cash	(249)	256
Net increase (decrease) in cash, cash equivalents and restricted cash	23,716	(1,691)
Cash, cash equivalents, and restricted cash at beginning of period (Note 2)	12,606	13,501
Cash, cash equivalents and restricted cash at end of period (Note 2)	36,322	11,810
Paycheck Protection Program CARES Act [Member]
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Gain of forgiveness on Paycheck Protection Plan Loan	(1,556)	0
Financing Activities
Proceeds from borrowings	$ 0	$ 1,556