Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
OPERATING ACTIVITIES
Net income (loss)	$ 157	$ (3,088)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation	1	486
Amortization of finite-lived intangible assets	15	56
Stock-based compensation	0	383
Realized loss (gain) on sale of marketable securities	4,316	(112)
Unrealized (gain) loss on marketable securities	(4,700)	4,561
Deferred income taxes	48	(1,146)
Changes in operating assets and liabilities:
Decrease (increase) in accounts receivable, net	270	(955)
Decrease (increase) in inventories, net	74	(2,092)
Decrease in prepaid expenses and other assets	212	284
Increase in accounts payable, accrued compensation, income taxes and commissions and other	61	792
Net cash provided by (used in) operating activities	454	(831)
INVESTING ACTIVITIES
Capital expenditures	0	(663)
Cash from consolidation of LGL Systems	1,869	0
Proceeds from sale of marketable securities	16,947	1,661
Purchase of marketable securities	0	(7,013)
Net cash provided by (used in) investing activities	18,816	(6,015)
FINANCING ACTIVITIES
Payment for taxes related to net share settlement of equity awards	0	(50)
Exercise of stock options	0	191
Prepaid financing costs	0	(20)
Net cash provided by financing activities	0	121
Increase (decrease) in cash and cash equivalents	19,270	(6,725)
Cash and cash equivalents at beginning of period	21,507	29,016
Cash and cash equivalents at end of period	40,777	22,291
Supplemental Disclosure:
Income taxes paid	$ 207	$ 741