Condensed Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows used in operating activities
Net loss	$ (9)	$ (2)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	40	90
Deferred income taxes	(6)	(7)
Stock-based compensation expense	1	1
Interest accrued on treasury bills	(1)	(2)
Change in:
Trade receivables	(150)	(252)
Inventories	(95)	4
Other current assets	(21)	(36)
Accounts payable	(23)	(7)
Accrued expenses	157	159
Income tax receivable/payable	1	7
Net cash used in operating activities	(106)	(45)
Cash flows from investing activities
Purchases of treasury bills	(1,999)	(4,999)
Proceeds from the maturity of treasury bills	3,000	5,000
Purchase of property and equipment	(3)	0
Net cash from investing activities	998	1
Cash flows used in financing activities
Payments on financing lease	(1)	(1)
Net cash used in financing activities	(1)	(1)
Net increase (decrease) in cash and cash equivalents	891	(45)
Cash and cash equivalents, beginning	6,713	1,090
Cash and cash equivalents, ending	7,604	1,045
Supplemental cash flow information
Cash paid for income taxes	$ 0	$ 0