Consolidated Statement of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating Activities:
Net income	$ 3,417	$ 3,750
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	3,019	2,870
Intangible asset amortization	144	885
Stock-based compensation	2,479	4,133
Loss on disposal of property and equipment	21	97
Restructuring costs	(29)	(33)
Bad debt recovery	(151)	(2)
Changes in operating assets and liabilities, net of acquisitions:
Accounts receivable	960	(1,532)
Inventories	2,076	873
Prepaid expenses and other assets	638	385
Accounts payable	1,086	(2,841)
Income taxes payable	(10)	(22)
Other accrued liabilities	(231)	2,263
Deferred revenue	1	92
Net cash provided by operating activities	13,420	10,918
Investing Activities:
Capital expenditures	(4,093)	(2,263)
Purchase of investments	(49,701)	(48,245)
Redemptions/maturities of short-term investments	47,035	46,559
Net cash used in investing activities	(6,759)	(3,949)
Financing Activities:
Proceeds from issuance of common stock	869	1,183
Proceeds from Paycheck Protection Program Loan	3,500	0
Repayment of Paycheck Protection Program Loan	(3,500)	0
Payment of withholding tax on stock-based compensation	(1,137)	(1,152)
Principle payments on finance leases	(78)	(99)
Purchase of common stock from repurchase program	(3,808)	0
Cash dividends	(4,108)	(4,068)
Net cash used in financing activities	(8,262)	(4,136)
Net (decrease) increase in cash and cash equivalents	(1,601)	2,833
Effect of exchange rate changes on cash	268	(68)
Cash and cash equivalents, beginning of year	7,094	4,329
Cash and Cash Equivalents, End of Year	5,761	7,094
Other information:
Cash paid for income taxes	29	34
Cash paid for interest	8	9
Non-cash investing and financing information:
Decreases to additional paid-in capital related to restricted stock	(188)	(1,037)
Issuance of restricted common stock, net of cancellations	28	226
Recognition of ROU assets under operating leases	2	2,116
Recognition of ROU assets under finance leases	$ 0	$ 118