v3.26.1
Financial Highlights Per Share Performance - Summary of Per Share Data (Details) - $ / shares
3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Investment Company, Financial Highlights [Roll Forward]    
Principal Market NAV, beginning of period $ 38.74 $ 41.39
Net decrease in net assets from investment operations:    
Net investment loss (0.01) (0.02)
Net realized and unrealized loss (8.74) (4.84)
Net decrease in net assets resulting from operations (8.75) (4.86)
Principal Market NAV, end of period $ 29.99 $ 36.53
Total return (22.59%) (11.74%)
Ratios to average net assets:    
Net investment loss 0.15% 0.15%
Expenses (0.15%) (0.15%)