Consolidated Statements of Operations - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
REVENUES	$ 524,000	$ 344,000	$ 370,000	$ 417,000	$ 361,000	$ 328,000	$ 475,000	$ 282,000	$ 1,655,000	$ 1,446,000
Type of Revenue [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Costs and expenses:
Manufacturing cost of sales	$ 165,000	$ 203,000	$ 227,000	$ 242,000	$ 215,000	$ 146,000	$ 206,000	$ 144,000	$ 837,000	$ 711,000
Engineering, selling and administrative	551,000	669,000	623,000	1,022,000	1,065,000	1,907,000	612,000	672,000	2,865,000	4,256,000
OPERATING (LOSS)	(192,000)	(528,000)	(480,000)	(847,000)	(919,000)	(1,725,000)	(343,000)	(534,000)	(2,047,000)	(3,521,000)
Other income (expense):
Interest income, net	137,000	52,000	9,000	(4,000)	1,000				194,000	1,000
Gain on equity investment in unconsolidated subsidiary						60,205,000	(676,000)	(76,000)		59,453,000
Realized loss on marketable securities									(22,649,000)	(16,962,000)
Unrealized gain (loss) on marketable securities									18,121,000	(22,949,000)
Other expenses, net	(29,000)	2,000	1,000	1,000	(259,000)	258,000	2,000	(1,000)	(25,000)
Total other (expense) income, net	29,000	(2,067,000)	(2,363,000)	42,000	(21,504,000)	41,596,000	(599,000)	50,000	(4,359,000)	19,543,000
(LOSS) INCOME BEFORE INCOME TAXES FOR CONTINUING OPERATIONS	(163,000)	(2,595,000)	(2,843,000)	(805,000)	(22,423,000)	39,871,000	(942,000)	(484,000)	(6,406,000)	16,022,000
(Benefit from) Provision for income taxes from continuing operations	(164,000)	(611,000)	(588,000)	(166,000)	(5,036,000)	8,823,000	(199,000)	(116,000)	(1,529,000)	3,472,000
Net (loss) income from continuing operations	1,000	(1,984,000)	(2,255,000)	(639,000)	(17,387,000)	31,048,000	(743,000)	(368,000)	(4,877,000)	12,550,000
Income from discontinued operations, net of tax	132,000	488,000	457,000	808,000	236,000	732,000	725,000	395,000	1,885,000	2,088,000
NET (LOSS) INCOME	$ 133,000	$ (1,496,000)	$ (1,798,000)	$ 169,000	$ (17,151,000)	$ 31,780,000	$ (18,000)	$ 27,000	$ (2,992,000)	$ 14,638,000
Net (Loss) Income per Basic Share:
Continuing Operations	$ 0.00	$ (0.37)	$ (0.42)	$ (0.12)	$ (3.29)	$ 5.89	$ (0.14)	$ (0.07)	$ (0.91)	$ 2.38
Discontinued Operations	0.02	0.09	0.09	0.15	0.04	0.14	0.14	0.07	0.35	0.40
Total Net (Loss) Income per Basic Share:	0.02	(0.28)	(0.34)	0.03	(3.25)	6.03		0.01	(0.56)	2.77
Net (Loss) Income per Diluted Share:
Continuing Operations	0.00	(0.37)	(0.42)	(0.12)	(3.29)	5.83	(0.14)	(0.07)	(0.91)	2.35
Discontinued Operations	0.02	0.09	0.09	0.15	0.04	0.14	$ 0.14	0.07	0.35	0.39
Total Net (Loss) Income per Diluted Share:	$ 0.02	$ (0.28)	$ (0.34)	$ 0.03	$ (3.25)	$ 5.97		$ 0.01	$ (0.56)	$ 2.74