SUPPLEMENTAL INFORMATION SELECTED PER SHARE DATA AND RATIOS (Unaudited) - $ / shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
SUPPLEMENTAL INFORMATION SELECTED PER SHARE DATA AND RATIOS (Unaudited)
Investment income	$ 0.09	$ 0.02	$ 0	$ 0	$ 0.02
Expenses	0.33	0.32	0.27	0.26	0.38
Net investment loss	(0.24)	(0.30)	(0.27)	(0.26)	(0.36)
Net realized gain (loss)	0.01	0.01	0	0.03	1.37
Net change in unrealized appreciation of portfolio securities	(1.15)	1.25	0.19	0.42	2.05
Net increase (decrease) in net assets resulting from operations	(1.38)	0.96	0.08	0.19	0.91
Capital transactions:
Shares issued for portfolio securities	0	0	0	0	0.01
Dilutive effect of shares issued	0	0.02	0	0	0
Increase in net assets resulting from capital transactions	0	(0.02)	0	0	0.01
Net increase (decrease) in net assets	(1.38)	0.94	0.08	0.19	0.90
Net assets at beginning of period	3.55	2.61	2.69	2.50	3.40
Net assets at end of period, basic and diluted	$ 2.17	$ 3.55	$ 2.61	$ 2.69	$ 2.50
Weighted average number of shares outstanding during period, in thousands	13,586	13,526	13,518	13,518	13,518
Market price per share:
Beginning of period	$ 1.45	$ 1.43	$ 2.38	$ 2.16	$ 1.82
End of period	$ 1.10	$ 1.45	$ 1.43	$ 2.38	$ 2.16
Selected information and ratios:
Ratio of expenses to average net assets	11.80%	8.87%	10.14%	9.77%	13.00%
Ratio of net investment loss to average net assets	(8.52%)	(8.36%)	(10.14%)	(9.77%)	(12.20%)
Ratio of net increase (decrease) in net assets resulting from operations to average net assets	(48.28%)	(26.82%)	(3.15%)	7.38%	(30.82%)
Total return on market price	(24.14%)	1.40%	(39.92%)	10.19%	18.68%