Condensed Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows used in operating activities
Net loss	$ (44)	$ (9)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	24	40
Deferred income taxes	(50)	(6)
Stock-based compensation expense	0	1
Interest accrued on treasury bills	(36)	(1)
Change in:
Trade receivables	(211)	(150)
Inventories	(34)	(95)
Other current assets	(1)	(21)
Accounts payable	83	(23)
Accrued expenses	73	157
Income tax receivable/payable	48	1
Net cash used in operating activities	(148)	(106)
Cash flows from (used in) investing activities
Purchases of treasury bills	(3,955)	(1,999)
Proceeds from the maturity of treasury bills	2,000	3,000
Purchase of property and equipment	(1)	(3)
Net cash from (used in) investing activities	(1,956)	998
Cash flows used in financing activities
Payments on financing lease	(2)	(1)
Net cash used in financing activities	(2)	(1)
Net increase (decrease) in cash and cash equivalents	(2,106)	891
Cash and cash equivalents, beginning	7,646	6,713
Cash and cash equivalents, ending	5,540	7,604
Supplemental cash flow information
Cash paid for income taxes	$ 0	$ 0