Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
OPERATING ACTIVITIES
Net income	$ 9	$ 438
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	233	224
Amortization of finite-lived intangible assets	38	37
Stock-based compensation	97	47
Loss from equity investment in unconsolidated subsidiary	752	139
Unrealized (gain) loss on marketable securities	(202)	107
Deferred income tax expense	56	112
Changes in operating assets and liabilities:
Increase in accounts receivable, net	(532)	(25)
Increase in inventories, net	(268)	(2)
(Increase) decrease in prepaid expenses and other assets	(33)	179
Decrease in accounts payable, accrued compensation and commissions and other	(102)	(385)
Net cash provided by operating activities	48	871
INVESTING ACTIVITIES
Subscription agreement funding (Note C)	(2,725)
Capital expenditures	(400)	(105)
Net cash used in investing activities	(3,125)	(105)
FINANCING ACTIVITIES
Net proceeds from revolving credit agreement		103
Proceeds from at-the-market stock sales		3,254
Proceeds from stock option exercise		63
Net cash provided by financing activities		3,420
(Decrease) increase in cash and cash equivalents	(3,077)	4,186
Cash and cash equivalents at beginning of period	18,331	12,453
Cash and cash equivalents at end of period	15,254	16,639
Supplemental Disclosure:
Cash paid for income taxes	$ 30	$ 30