v3.26.1
Schedule of Investments (Parenthetical) - USD ($)
 6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
United States Commodity Index Fund    
% of Partners' Capital 0.37% [1] (0.96%) [2]
Collateral amount $ 24,685,967 $ 17,113,637
Expiration date 7 days 7 days
United States Commodity Index Fund | Dreyfus Institutional Preferred Government Money Market Fund - Institutional Shares, 3.60%    
Interest rate on money market fund (as a percent) 3.60%  
United States Commodity Index Fund | Dreyfus Institutional Preferred Government Money Market Fund - Institutional Shares, 3.71%    
Interest rate on money market fund (as a percent)   3.71%
United States Commodity Index Fund | Cash Equivalents    
% of Partners' Capital 83.48%  
United States Commodity Index Fund | Cash Equivalents | Matures on 7/02/2026, yield 3.64%    
Interest rate on money market fund (as a percent) 3.64%  
United States Commodity Index Fund | Cash Equivalents | Matures on 7/09/2026, yield 3.70%    
Interest rate on money market fund (as a percent) 3.70%  
United States Commodity Index Fund | Cash Equivalents | Matures on 7/16/2026, yield 3.70%    
Interest rate on money market fund (as a percent) 3.70%  
United States Commodity Index Fund | Cash Equivalents | Matures on 8/20/2026, yield 3.61%    
Interest rate on money market fund (as a percent) 3.61%  
United States Commodity Index Fund | Cash Equivalents | Matures on 9/03/2026, yield 3.66%    
Interest rate on money market fund (as a percent) 3.66%  
United States Commodity Index Fund | Cash Equivalents | Matures on 9/10/2026, yield 3.70%    
Interest rate on money market fund (as a percent) 3.70%  
United States Commodity Index Fund | Cash Equivalents | Matures on 9/22/2026, yield 3.54%    
Interest rate on money market fund (as a percent) 3.54%  
United States Commodity Index Fund | Cash Equivalents | Matures on 9/29/2026, yield 3.68%    
Interest rate on money market fund (as a percent) 3.68%  
United States Commodity Index Fund | Cash Equivalents | Matures on 12/10/2026, yield 3.72%    
Interest rate on money market fund (as a percent) 3.72%  
United States Commodity Index Fund | Money Market Funds    
% of Partners' Capital 58.71% 75.46%
United States Commodity Index Fund | Money Market Funds | Dreyfus Institutional Preferred Government Money Market Fund - Institutional Shares, 3.60%    
% of Partners' Capital [3] 58.71%  
United States Commodity Index Fund | Money Market Funds | Dreyfus Institutional Preferred Government Money Market Fund - Institutional Shares, 3.71%    
% of Partners' Capital [4]   75.46%
United States Copper Index Fund    
Collateral amount $ 73,596,659 $ 0
Expiration date 7 days 7 days
United States Copper Index Fund | Dreyfus Institutional Preferred Government Money Market Fund - Institutional Shares, 3.60%    
Interest rate 3.60%  
United States Copper Index Fund | Dreyfus Institutional Preferred Government Money Market Fund - Institutional Shares, 3.71%    
Interest rate on money market fund (as a percent)   3.71%
United States Copper Index Fund | Cash Equivalents    
% of Partners' Capital 87.52%  
United States Copper Index Fund | Cash Equivalents | Matures on 7/02/2026, yield 3.64%    
Interest rate on money market fund (as a percent) 3.64%  
United States Copper Index Fund | Cash Equivalents | Matures on 7/09/2026, yield 3.70%    
Interest rate on money market fund (as a percent) 3.70%  
United States Copper Index Fund | Cash Equivalents | Matures on 7/14/2026, yield 3.71%    
Interest rate on money market fund (as a percent) 3.71%  
United States Copper Index Fund | Cash Equivalents | Matures on 7/16/2026, yield 3.70%    
Interest rate on money market fund (as a percent) 3.70%  
United States Copper Index Fund | Cash Equivalents | Matures on 8/20/2026, yield 3.61%    
Interest rate on money market fund (as a percent) 3.61%  
United States Copper Index Fund | Cash Equivalents | Matures on 9/08/2026, yield 3.71%    
Interest rate on money market fund (as a percent) 3.71%  
United States Copper Index Fund | Cash Equivalents | Matures on 9/10/2026, yield 3.57%    
Interest rate on money market fund (as a percent) 3.57%  
United States Copper Index Fund | Cash Equivalents | Matures on 9/22/2026, yield 3.54%    
Interest rate on money market fund (as a percent) 3.54%  
United States Copper Index Fund | Cash Equivalents | Matures on 9/29/2026, yield 3.68%    
Interest rate on money market fund (as a percent) 3.68%  
United States Copper Index Fund | Cash Equivalents | Matures on 10/06/2026, yield 3.72%    
Interest rate on money market fund (as a percent) 3.72%  
United States Copper Index Fund | Cash Equivalents | Matures on 10/13/2026, yield 3.73%    
Interest rate on money market fund (as a percent) 3.73%  
United States Copper Index Fund | Cash Equivalents | Matures on 11/19/2026, yield 3.78%    
Interest rate on money market fund (as a percent) 3.78%  
United States Copper Index Fund | Cash Equivalents | Matures on 12/03/2026, yield 3.81%    
Interest rate on money market fund (as a percent) 3.81%  
United States Copper Index Fund | Cash Equivalents | Matures on 12/10/2026, yield 3.67%    
Interest rate on money market fund (as a percent) 3.67%  
United States Copper Index Fund | Money Market Funds    
% of Partners' Capital 62.17% 64.96%
United States Copper Index Fund | Money Market Funds | Dreyfus Institutional Preferred Government Money Market Fund - Institutional Shares, 3.60%    
% of Partners' Capital [3] 62.17%  
United States Copper Index Fund | Money Market Funds | Dreyfus Institutional Preferred Government Money Market Fund - Institutional Shares, 3.71%    
% of Partners' Capital [4]   64.96%
United States Copper Index Fund | Open Commodity Futures Contracts - Long    
% of Partners' Capital (0.21%) [5] 11.45% [6]
ICE Low Sulphur Gasoil Futures QS May 2026 contracts, expiring May 2026 | United States Commodity Index Fund | Open Commodity Futures Contracts - Long | United Kingdom Contracts    
% of Partners' Capital [7]   0.00%
ICE Low Sulphur Gasoil Futures QS May 2026 contracts, expiring May 2026 | United States Copper Index Fund | Open Commodity Futures Contracts - Long | United Kingdom Contracts | Maximum    
% of Partners' Capital   0.005%
[1] Collateral amounted to $24,685,967 on open commodity futures contracts.
[2] Collateral amounted to $17,113,637 on open commodity futures contracts.
[3] Reflects the 7-day yield at June 30, 2026.
[4] Reflects the 7-day yield at December 31, 2025.
[5] Collateral amounted to $73,596,659 on open commodity futures contracts.
[6] Collateral amounted to $0 on open commodity futures contracts.
[7] Represents less than 0.005%.