Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
OPERATING ACTIVITIES
Net income (loss)	$ 27	$ (1,629)
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Depreciation	1	313
Amortization of finite-lived intangible assets	6	38
Stock-based compensation	0	303
Realized loss (gain) on sale of marketable securities	4,316	(112)
Unrealized (loss) gain on marketable securities	(4,703)	2,441
Deferred income taxes	18	(589)
Changes in operating assets and liabilities:
Decrease (increase) in accounts receivable, net	170	(44)
Decrease (increase) in inventories, net	39	(880)
Decrease in prepaid expenses and other assets	185	168
Decrease in accounts payable, accrued compensation, income taxes and commissions and other	(68)	(896)
Net cash used in operating activities	(9)	(887)
INVESTING ACTIVITIES
Capital expenditures	0	(395)
Cash from consolidation of LGL Systems	1,869	0
Proceeds from sale of marketable securities	16,947	1,661
Purchase of marketable securities	0	(7,000)
Net cash provided by (used in) investing activities	18,816	(5,734)
FINANCING ACTIVITIES
Payment for taxes related to net share settlement of equity awards	0	(50)
Prepaid financing costs	0	(20)
Net cash provided by financing activities	0	(70)
Decrease in cash and cash equivalents	18,807	(6,691)
Cash and cash equivalents at beginning of period	21,507	29,016
Cash and cash equivalents at end of period	40,314	22,325
Supplemental Disclosure:
Income taxes paid	$ 134	$ 735