FINANCIAL HIGHLIGHTS (Details) - $ / shares	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Per Share Operating Performance:
Net asset value, beginning of period	$ 15.31	$ 17.39	$ 16.85	$ 20.36
Total income (loss)	(2.3)	(0.91)	(3.74)	(3.78)
Total expenses	(0.04)	(0.05)	(0.14)	(0.15)
Net increase (decrease) in net asset value	(2.34)	(0.96)	(3.88)	(3.93)
Net asset value, end of period	$ 12.97	$ 16.43	$ 12.97	$ 16.43
Total Return	(15.28%)	(5.52%)	(23.03%)	(19.30%)
Ratios to Average Net Assets
Total income (loss)	(10.88%)	0.56%	7.05%	2.35%
Management fees	0.60%	0.60%	0.60%	0.60%
Total expenses excluding management fees	0.49%	0.66%	0.59%	0.66%
Net income (loss)	(11.15%)	0.24%	6.15%	1.41%