Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
OPERATING ACTIVITIES
Net income	$ 157	$ 169
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation	0	148
Amortization of finite-lived intangible assets	5	18
Stock-based compensation	0	233
Realized loss on sale of marketable securities	2,102	744
Unrealized gain on marketable securities	(2,447)	(789)
Deferred income taxes	28	(165)
Changes in operating assets and liabilities:
Decrease (increase) in accounts receivable, net	34	(588)
Decrease (increase) in inventories, net	28	(427)
(Increase) decrease in prepaid expenses and other assets	(111)	31
Increase in accounts payable, accrued compensation, income taxes and commissions and other	154	72
Net cash used in operating activities	(50)	(554)
INVESTING ACTIVITIES
Capital expenditures	0	(207)
Proceeds from sale of marketable securities	43	397
Purchase of marketable securities	0	(7,000)
Net cash provided by (used in) investing activities	43	(6,810)
Decrease in cash and cash equivalents	(7)	(7,364)
Cash and cash equivalents at beginning of period	21,507	29,016
Cash and cash equivalents at end of period	21,500	21,652
Supplemental Disclosure:
Income taxes paid	$ 134	$ 50