Schedule of Investments (USD $)
Dec. 31, 2013
Dec. 31, 2012
contract
Number of Contracts 13,573 [1]  
Unrealized Gain (Loss) on Open Commodity Contracts $ 10,789,747 [1]  
United States Commodity Index Fund [Member]
    
Number of Contracts   13,041 [1]
Unrealized Gain (Loss) on Open Commodity Contracts   (5,220,900) [1]
% of Capital 2.10% [1] (1.07%) [1]
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | US Treasury Securities [Member]
    
Number of Contracts 5,500  
Unrealized Gain (Loss) on Open Commodity Contracts 4,571,285  
% of Capital 0.89%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | US Treasury Securities [Member] | CME Feeder Cattle Futures FC March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 441  
Unrealized Gain (Loss) on Open Commodity Contracts (64,763)  
% of Capital (0.01%)  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | US Treasury Securities [Member] | COMEX Copper Futures HG March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 434  
Unrealized Gain (Loss) on Open Commodity Contracts 1,984,638  
% of Capital 0.39%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | US Treasury Securities [Member] | CME Live Cattle Futures LC February 2014 contracts, expiring February 2014 [Member]
    
Number of Contracts 687  
Unrealized Gain (Loss) on Open Commodity Contracts 335,850  
% of Capital 0.07%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | US Treasury Securities [Member] | NYMEX Natural Gas Futures NG April 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 873  
Unrealized Gain (Loss) on Open Commodity Contracts (710,860)  
% of Capital (0.14%)  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | US Treasury Securities [Member] | NYMEX WTI Crude Oil Futures CL April 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 371  
Unrealized Gain (Loss) on Open Commodity Contracts 2,175,700  
% of Capital 0.42%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | US Treasury Securities [Member] | NYMEX Heating Oil Futures HO June 2014 contracts, expiring May 2014 [Member]
    
Number of Contracts 289  
Unrealized Gain (Loss) on Open Commodity Contracts 1,411,965  
% of Capital 0.27%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | US Treasury Securities [Member] | CBOT Soybean Futures S November 2014 contracts, expiring November 2014 [Member]
    
Number of Contracts 640  
Unrealized Gain (Loss) on Open Commodity Contracts (902,100)  
% of Capital (0.18%)  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | US Treasury Securities [Member] | NYMEX Platinum Futures PL April 2014 contracts, expiring April 2014 [Member]
    
Number of Contracts 540  
Unrealized Gain (Loss) on Open Commodity Contracts 162,485  
% of Capital 0.03%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | US Treasury Securities [Member] | CBOT Soybean Meal Futures SM May 2014 contracts, expiring May 2014 [Member]
    
Number of Contracts 889  
Unrealized Gain (Loss) on Open Commodity Contracts (58,640)  
% of Capital (0.01%)  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | US Treasury Securities [Member] | NYMEX RBOB Gasoline Futures RB December 2014 contracts, expiring November [Member]
    
Number of Contracts 336  
Unrealized Gain (Loss) on Open Commodity Contracts 237,010  
% of Capital 0.05%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member]
    
Number of Contracts 5,508 5,872
Unrealized Gain (Loss) on Open Commodity Contracts 12,047,859 (2,740,550)
% of Capital 2.35% (0.56%)
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-US Cotton #2 Futures CT July 2014 contracts, expiring July 2014 [Member]
    
Number of Contracts 892  
Unrealized Gain (Loss) on Open Commodity Contracts 1,753,955  
% of Capital 0.34%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Tin Futures LT March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 402  
Unrealized Gain (Loss) on Open Commodity Contracts 4,337,905  
% of Capital 0.85%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Lead Futures LL April 2014 contracts, expiring April 2014 [Member]
    
Number of Contracts 711  
Unrealized Gain (Loss) on Open Commodity Contracts 117,525  
% of Capital 0.02%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Zinc Futures LX April 2014 contracts, expiring April 2014 [Member]
    
Number of Contracts 790  
Unrealized Gain (Loss) on Open Commodity Contracts 1,505,606  
% of Capital 0.29%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-US Cocoa Futures CC May 2014 contracts, expiring May 2014 [Member]
    
Number of Contracts 1,323  
Unrealized Gain (Loss) on Open Commodity Contracts 1,161,220  
% of Capital 0.23%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE Brent Crude Oil Futures CO June 2014 contracts, expiring May 2014 [Member]
    
Number of Contracts 334  
Unrealized Gain (Loss) on Open Commodity Contracts 3,288,860  
% of Capital 0.64%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-UK Gasoil Futures QS June 2014 contracts, expiring June 2014 [Member]
    
Number of Contracts 394  
Unrealized Gain (Loss) on Open Commodity Contracts (160,025)  
% of Capital (0.03%)  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Lead Futures LL June 2014 contracts, expiring June 2014 [Member]
    
Number of Contracts 662  
Unrealized Gain (Loss) on Open Commodity Contracts 42,813  
% of Capital 0.01%  
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Aluminum Futures LA January 2013 contracts, expiring January 2013 [Member]
    
Number of Contracts   1,188
Unrealized Gain (Loss) on Open Commodity Contracts   (198,244)
% of Capital   (0.04%)
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE Brent Crude Oil Futures CO March 2013 contracts, expiring February 2013 [Member]
    
Number of Contracts   318
Unrealized Gain (Loss) on Open Commodity Contracts   18,170
% of Capital   0.00%
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-US Cocoa Futures CC March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   1,545
Unrealized Gain (Loss) on Open Commodity Contracts   (2,233,750)
% of Capital   (0.46%)
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Aluminum Futures LA March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   506
Unrealized Gain (Loss) on Open Commodity Contracts   (4,449,450)
% of Capital   (0.91%)
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-UK Gasoil Futures QS June 2013 contracts, expiring June 2013 [Member]
    
Number of Contracts   377
Unrealized Gain (Loss) on Open Commodity Contracts   (390,900)
% of Capital   (0.08%)
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Tin Futures LT August 2013 contracts, expiring August 2013 [Member]
    
Number of Contracts   300
Unrealized Gain (Loss) on Open Commodity Contracts   31,470
% of Capital   0.01%
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Zinc Futures LX August 2013 contracts, expiring August 2013 [Member]
    
Number of Contracts   667
Unrealized Gain (Loss) on Open Commodity Contracts   (87,644)
% of Capital   (0.02%)
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Lead Futures LL February 2013 contracts, expiring February 2013 [Member]
    
Number of Contracts   638
Unrealized Gain (Loss) on Open Commodity Contracts   1,602,863
% of Capital   0.33%
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member]
    
Number of Contracts   5,100
Unrealized Gain (Loss) on Open Commodity Contracts   (8,122,385)
% of Capital   (1.67%)
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Corn Futures C December 2013 contracts, expiring December 2013 [Member]
    
Number of Contracts   1,167
Unrealized Gain (Loss) on Open Commodity Contracts   (1,967,400)
% of Capital   (0.40%)
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Soybean Futures S November 2013 contracts, expiring November 2013 [Member]
    
Number of Contracts   538
Unrealized Gain (Loss) on Open Commodity Contracts   (713,900)
% of Capital   (0.15%)
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Soybean Meal Futures SM March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   816
Unrealized Gain (Loss) on Open Commodity Contracts   (2,982,000)
% of Capital   (0.61%)
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CME Live Cattle Futures LC April 2013 contracts, expiring April 2013 [Member]
    
Number of Contracts   637
Unrealized Gain (Loss) on Open Commodity Contracts   239,880
% of Capital   0.05%
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | NYMEX Heating Oil Futures HO April 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   278
Unrealized Gain (Loss) on Open Commodity Contracts   32,936
% of Capital   0.01%
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | NYMEX Platinum Futures PL April 2013 contracts, expiring April 2013 [Member]
    
Number of Contracts   454
Unrealized Gain (Loss) on Open Commodity Contracts   171,375
% of Capital   0.03%
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Wheat Futures W July 2013 contracts, expiring July 2013 [Member]
    
Number of Contracts   884
Unrealized Gain (Loss) on Open Commodity Contracts   (2,896,875)
% of Capital   (0.60%)
United States Commodity Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | NYMEX RBOB Gasoline Futures XB December 2013 contracts, expiring November 2013 [Member]
    
Number of Contracts   326
Unrealized Gain (Loss) on Open Commodity Contracts   (6,401)
% of Capital   0.00%
United States Commodity Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member]
    
Number of Contracts 2,565 [2] 2,069 [2]
Unrealized Gain (Loss) on Open Commodity Contracts (5,829,397) [2] 5,642,035 [2]
% of Capital (1.14%) [2] 1.16% [2]
United States Commodity Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Tin Futures LT March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 402 [2]  
Unrealized Gain (Loss) on Open Commodity Contracts 645,975 [2]  
% of Capital 0.13% [2]  
United States Commodity Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Lead Futures LL April 2014 contracts, expiring April 2014 [Member]
    
Number of Contracts 711 [2]  
Unrealized Gain (Loss) on Open Commodity Contracts (1,932,074) [2]  
% of Capital (0.38%) [2]  
United States Commodity Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Zinc Futures LX April 2014 contracts, expiring April 2014 [Member]
    
Number of Contracts 790 [2]  
Unrealized Gain (Loss) on Open Commodity Contracts (2,435,467) [2]  
% of Capital (0.48%) [2]  
United States Commodity Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Lead Futures LL June 2014 contracts, expiring June 2014 [Member]
    
Number of Contracts 662 [2]  
Unrealized Gain (Loss) on Open Commodity Contracts (2,107,831) [2]  
% of Capital (0.41%) [2]  
United States Commodity Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Aluminum Futures LA January 2013 contracts, expiring January 2013 [Member]
    
Number of Contracts   1,188 [2]
Unrealized Gain (Loss) on Open Commodity Contracts   3,591,081 [2]
% of Capital   0.74% [2]
United States Commodity Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Aluminum Futures LA March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   506 [2]
Unrealized Gain (Loss) on Open Commodity Contracts   2,087,289 [2]
% of Capital   0.43% [2]
United States Commodity Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Tin Futures LT August 2013 contracts, expiring August 2013 [Member]
    
Number of Contracts   1 [2]
Unrealized Gain (Loss) on Open Commodity Contracts   (427) [2]
% of Capital   0.00% [2]
United States Commodity Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Zinc Futures LX August 2013 contracts, expiring August 2013 [Member]
    
Number of Contracts   5 [2]
Unrealized Gain (Loss) on Open Commodity Contracts   (2,487) [2]
% of Capital   0.00% [2]
United States Commodity Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Lead Futures LL February 2013 contracts, expiring February 2013 [Member]
    
Number of Contracts   36 [2]
Unrealized Gain (Loss) on Open Commodity Contracts   3,227 [2]
% of Capital   0.00% [2]
United States Commodity Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Tin Futures LT January 2013 contracts, expiring January 2013 [Member]
    
Number of Contracts   333 [2]
Unrealized Gain (Loss) on Open Commodity Contracts   (36,648) [2]
% of Capital   (0.01%) [2]
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member]
    
Market Value 325,142,075 435,149,105
% of Capital 63.39% 89.15%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.04%, 3/06/2014 [Member]
    
Principal Amount 30,200,000  
Market Value 30,197,808  
% of Capital 5.89%  
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.05%, 3/27/2014 [Member]
    
Principal Amount 30,000,000  
Market Value 29,996,813  
% of Capital 5.85%  
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.05%, 1/09/2014 [Member]
    
Principal Amount 55,000,000  
Market Value 54,999,318  
% of Capital 10.72%  
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.06%, 1/09/2014 [Member]
    
Principal Amount 20,000,000  
Market Value 19,999,752  
% of Capital 3.90%  
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.04%, 1/30/2014 [Member]
    
Principal Amount 20,000,000  
Market Value 19,999,285  
% of Capital 3.90%  
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 1/03/2013 [Member]
    
Principal Amount   40,000,000
Market Value   39,999,800
% of Capital   8.19%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 1/10/2013 [Member]
    
Principal Amount   10,000,000
Market Value   9,999,781
% of Capital   2.05%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 1/17/2013 [Member]
    
Principal Amount   10,000,000
Market Value   9,999,573
% of Capital   2.05%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.10%, 1/17/2013 [Member]
    
Principal Amount   10,000,000
Market Value   9,999,573
% of Capital   2.05%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 1/24/2013 [Member]
    
Principal Amount   45,000,000
Market Value   44,997,423
% of Capital   9.22%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 2/07/2013 [Member]
    
Principal Amount   40,000,000
Market Value   39,996,402
% of Capital   8.19%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.06%, 2/28/2013 [Member]
    
Principal Amount   20,200,000
Market Value   20,197,966
% of Capital   4.14%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.07%, 3/07/2013 [Member]
    
Principal Amount   20,000,000
Market Value   19,996,967
% of Capital   4.10%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 3/07/2013 [Member]
    
Principal Amount   50,000,000
Market Value   49,992,418
% of Capital   10.24%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.05%, 3/14/2013 [Member]
    
Principal Amount   20,000,000
Market Value   19,998,180
% of Capital   4.10%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.10%, 3/28/2013 [Member]
    
Principal Amount   50,000,000
Market Value   49,988,223
% of Capital   10.24%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.04%, 4/18/2013 [Member]
    
Principal Amount   90,000,000
Market Value   89,988,765
% of Capital   18.44%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.06%, 5/02/2013 [Member]
    
Principal Amount 20,000,000 30,000,000
Market Value 19,996,614 29,994,034
% of Capital 3.90% 6.14%
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.07%, 4/24/2014 [Member]
    
Principal Amount 20,000,000  
Market Value 19,995,606  
% of Capital 3.90%  
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.08%, 5/01/2014 [Member]
    
Principal Amount 20,000,000  
Market Value 19,995,000  
% of Capital 3.90%  
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.08%, 5/08/2014 [Member]
    
Principal Amount 30,000,000  
Market Value 29,991,533  
% of Capital 5.85%  
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 5/15/2014 [Member]
    
Principal Amount 30,000,000  
Market Value 29,989,950  
% of Capital 5.84%  
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.10%, 6/05/2014 [Member]
    
Principal Amount 30,000,000  
Market Value 29,987,729  
% of Capital 5.84%  
United States Commodity Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.08%, 6/26/2014 [Member]
    
Principal Amount 20,000,000  
Market Value 19,992,667  
% of Capital 3.90%  
United States Copper Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member]
    
Number of Contracts   28 [3]
Unrealized Gain (Loss) on Open Commodity Contracts   6,575 [3]
% of Capital   0.26% [3]
United States Copper Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | COMEX Copper Futures HG December 2013 contracts, expiring December 2013 [Member]
    
Number of Contracts   14
Unrealized Gain (Loss) on Open Commodity Contracts   (1,675)
% of Capital   (0.07%)
United States Copper Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | COMEX Copper Futures HG March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 27  
Unrealized Gain (Loss) on Open Commodity Contracts 130,163  
% of Capital 5.68%  
United States Copper Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | COMEX Copper Futures HG March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   7
Unrealized Gain (Loss) on Open Commodity Contracts   8,575
% of Capital   0.34%
United States Copper Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | COMEX Copper Futures HG May 2013 contracts, expiring May 2013 [Member]
    
Number of Contracts   7
Unrealized Gain (Loss) on Open Commodity Contracts   (325)
% of Capital   (0.01%)
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member]
    
Market Value 1,599,705 2,149,689
% of Capital 69.79% 84.54%
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.06%, 1/09/2014 [Member]
    
Principal Amount 100,000  
Market Value 99,999  
% of Capital 4.36%  
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.05%, 3/06/2014 [Member]
    
Principal Amount 400,000  
Market Value 399,968  
% of Capital 17.45%  
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.05%, 3/27/2014 [Member]
    
Principal Amount 100,000  
Market Value 99,989  
% of Capital 4.36%  
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 1/03/2013 [Member]
    
Principal Amount   150,000
Market Value   149,999
% of Capital   5.90%
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 2/07/2013 [Member]
    
Principal Amount   100,000
Market Value   99,991
% of Capital   3.93%
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.06%, 2/28/2013 [Member]
    
Principal Amount   100,000
Market Value   99,990
% of Capital   3.93%
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.10%, 3/28/2013 [Member]
    
Principal Amount   500,000
Market Value   499,882
% of Capital   19.66%
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.04%, 4/18/2013 [Member]
    
Principal Amount   300,000
Market Value   299,962
% of Capital   11.80%
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.06%, 4/17/2014 [Member]
    
Principal Amount 200,000  
Market Value 199,966  
% of Capital 8.73%  
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.06%, 5/02/2013 [Member]
    
Principal Amount   200,000
Market Value   199,960
% of Capital   7.86%
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.07%, 4/24/2014 [Member]
    
Principal Amount 200,000 200,000
Market Value 199,956 199,984
% of Capital 8.73% 7.87%
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.08%, 5/01/2014 [Member]
    
Principal Amount 200,000  
Market Value 199,950  
% of Capital 8.72%  
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.08%, 5/08/2014 [Member]
    
Principal Amount 200,000  
Market Value 199,944  
% of Capital 8.72%  
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 5/15/2014 [Member]
    
Principal Amount 200,000  
Market Value 199,933  
% of Capital 8.72%  
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.08%, 1/03/2013 [Member]
    
Principal Amount   100,000
Market Value   100,000
% of Capital   3.93%
United States Copper Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 3/07/2012 [Member]
    
Principal Amount   500,000
Market Value   499,921
% of Capital   19.66%
United States Agriculture Index Fund [Member]
    
Number of Contracts 68 [4] 72 [5]
Unrealized Gain (Loss) on Open Commodity Contracts (44,533) [4] (119,155) [5]
% of Capital (1.95%) [4] (4.66%) [5]
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member]
    
Number of Contracts 29 29
Unrealized Gain (Loss) on Open Commodity Contracts 2,216 (31,470)
% of Capital 0.10% (1.23%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-US Cotton #2 Futures CT July 2014 contracts, expiring July 2014 [Member]
    
Number of Contracts 5  
Unrealized Gain (Loss) on Open Commodity Contracts 9,520  
% of Capital 0.42%  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-Canola Futures RS March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 3  
Unrealized Gain (Loss) on Open Commodity Contracts (1,951)  
% of Capital (0.09%)  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-US Sugar #11 Futures SB May 2014 contracts, expiring April 2014 [Member]
    
Number of Contracts 10  
Unrealized Gain (Loss) on Open Commodity Contracts (9,408)  
% of Capital (0.41%)  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-US Cocoa Futures CC March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   4
Unrealized Gain (Loss) on Open Commodity Contracts   (9,740)
% of Capital   (0.38%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-US Coffee-C Futures KC July 2014 contracts, expiring July 2014 [Member]
    
Number of Contracts 4  
Unrealized Gain (Loss) on Open Commodity Contracts 675  
% of Capital 0.03%  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-US Cocoa Futures CC July 2014 contracts, expiring July 2014 [Member]
    
Number of Contracts 7  
Unrealized Gain (Loss) on Open Commodity Contracts 3,380  
% of Capital 0.15%  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-Canola Futures RS March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   10
Unrealized Gain (Loss) on Open Commodity Contracts   (4,137)
% of Capital   (0.16%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-US Cotton Futures CT March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   2
Unrealized Gain (Loss) on Open Commodity Contracts   1,035
% of Capital   0.04%
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-US Sugar #11 Futures SB May 2013 contracts, expiring April 2013 [Member]
    
Number of Contracts   9
Unrealized Gain (Loss) on Open Commodity Contracts   (515)
% of Capital   (0.02%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | ICE-US Coffee-C Futures KC July 2013 contracts, expiring July 2013 [Member]
    
Number of Contracts   4
Unrealized Gain (Loss) on Open Commodity Contracts   (18,113)
% of Capital   (0.71%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member]
    
Number of Contracts 39 43
Unrealized Gain (Loss) on Open Commodity Contracts (46,749) (87,685)
% of Capital (2.05%) (3.43%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CME Feeder Cattle Futures FC March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 1  
Unrealized Gain (Loss) on Open Commodity Contracts (525)  
% of Capital (0.02%)  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CME Live Cattle Futures LC February 2014 contracts, expiring February 2014 [Member]
    
Number of Contracts 5  
Unrealized Gain (Loss) on Open Commodity Contracts 1,970  
% of Capital 0.09%  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Corn Futures C December 2013 contracts, expiring December 2013 [Member]
    
Number of Contracts   11
Unrealized Gain (Loss) on Open Commodity Contracts   (20,475)
% of Capital   (0.80%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Soybean Oil Futures BO March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 1  
Unrealized Gain (Loss) on Open Commodity Contracts (84)  
% of Capital 0.00%  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Wheat Futures W March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 5  
Unrealized Gain (Loss) on Open Commodity Contracts (14,513)  
% of Capital (0.64%)  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Soybean Futures S November 2014 contracts, expiring November 2014 [Member]
    
Number of Contracts 6  
Unrealized Gain (Loss) on Open Commodity Contracts (11,325)  
% of Capital (0.50%)  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Soybean Futures S November 2013 contracts, expiring November 2013 [Member]
    
Number of Contracts   6
Unrealized Gain (Loss) on Open Commodity Contracts   (3,250)
% of Capital   (0.13%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Soybean Meal Futures SM May 2014 contracts, expiring May 2014 [Member]
    
Number of Contracts 4  
Unrealized Gain (Loss) on Open Commodity Contracts 970  
% of Capital 0.04%  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Soybean Meal Futures SM March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   5
Unrealized Gain (Loss) on Open Commodity Contracts   (15,730)
% of Capital   (0.61%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CME Live Cattle Futures LC April 2013 contracts, expiring April 2013 [Member]
    
Number of Contracts   5
Unrealized Gain (Loss) on Open Commodity Contracts   1,360
% of Capital   0.05%
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | KCBOT Hard Red Winter Wheat Futures KW May 2014 contracts, expiring May 2014 [Member]
    
Number of Contracts 1  
Unrealized Gain (Loss) on Open Commodity Contracts (4,900)  
% of Capital (0.22%)  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Corn Futures C December 2014 contracts, expiring December 2014 [Member]
    
Number of Contracts 11  
Unrealized Gain (Loss) on Open Commodity Contracts (12,362)  
% of Capital (0.54%)  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CME Lean Hogs Futures LH April 2014 contracts, expiring April 2014 [Member]
    
Number of Contracts 5  
Unrealized Gain (Loss) on Open Commodity Contracts (5,980)  
% of Capital (0.26%)  
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Wheat Futures W March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   7
Unrealized Gain (Loss) on Open Commodity Contracts   (32,525)
% of Capital   (1.27%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CME Feeder Cattle Futures FC March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   1
Unrealized Gain (Loss) on Open Commodity Contracts   (412)
% of Capital   (0.02%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CME Lean Hogs Futures LH April 2013 contracts, expiring April 2013 [Member]
    
Number of Contracts   3
Unrealized Gain (Loss) on Open Commodity Contracts   (2,970)
% of Capital   (0.12%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | KCBT Hard Red Winter Wheat Futures KW May 2013 contracts, expiring May 2013 [Member]
    
Number of Contracts   4
Unrealized Gain (Loss) on Open Commodity Contracts   (13,275)
% of Capital   (0.52%)
United States Agriculture Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CBOT Soybean Oil Futures BO July 2013 contracts, expiring July 2013 [Member]
    
Number of Contracts   1
Unrealized Gain (Loss) on Open Commodity Contracts   (408)
% of Capital   (0.01%)
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member]
    
Market Value 1,499,678 2,199,688
% of Capital 65.81% 86.07%
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.05%, 3/06/2014 [Member]
    
Principal Amount 200,000  
Market Value 199,984  
% of Capital 8.78%  
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.05%, 3/27/2014 [Member]
    
Principal Amount 200,000  
Market Value 199,979  
% of Capital 8.78%  
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 1/03/2013 [Member]
    
Principal Amount   150,000
Market Value   149,999
% of Capital   5.87%
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 1/17/2013 [Member]
    
Principal Amount   200,000
Market Value   199,992
% of Capital   7.83%
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.10%, 3/28/2013 [Member]
    
Principal Amount   500,000
Market Value   499,882
% of Capital   19.56%
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.04%, 4/18/2013 [Member]
    
Principal Amount   400,000
Market Value   399,950
% of Capital   15.65%
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.06%, 4/17/2014 [Member]
    
Principal Amount 200,000  
Market Value 199,966  
% of Capital 8.78%  
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.07%, 4/24/2014 [Member]
    
Principal Amount 200,000 200,000
Market Value 199,956 199,984
% of Capital 8.77% 7.82%
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.08%, 5/01/2014 [Member]
    
Principal Amount 200,000  
Market Value 199,950  
% of Capital 8.77%  
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.08%, 5/08/2014 [Member]
    
Principal Amount 200,000  
Market Value 199,944  
% of Capital 8.77%  
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 5/15/2014 [Member]
    
Principal Amount 300,000  
Market Value 299,899  
% of Capital 13.16%  
United States Agriculture Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.09%, 3/07/2012 [Member]
    
Principal Amount   750,000
Market Value   749,881
% of Capital   29.34%
United States Metals Index Fund [Member]
    
Number of Contracts 105 [6] 84 [7]
Unrealized Gain (Loss) on Open Commodity Contracts (46,293) [6] 46,058 [7]
% of Capital (2.11%) [6] 1.74% [7]
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member]
    
Number of Contracts 52 43
Unrealized Gain (Loss) on Open Commodity Contracts (45,618) 125,708
% of Capital (2.08%) 4.75%
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Tin Futures LT March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 4  
Unrealized Gain (Loss) on Open Commodity Contracts 9,460  
% of Capital 0.43%  
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Lead Futures LL April 2014 contracts, expiring April 2014 [Member]
    
Number of Contracts 6  
Unrealized Gain (Loss) on Open Commodity Contracts 81  
% of Capital 0.00%  
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Aluminum Futures LA January 2014 contracts, expiring January 2014 [Member]
    
Number of Contracts 15  
Unrealized Gain (Loss) on Open Commodity Contracts (71,431)  
% of Capital (3.25%)  
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Zinc Futures LX January 2014 contracts, expiring January 2014 [Member]
    
Number of Contracts 10  
Unrealized Gain (Loss) on Open Commodity Contracts 31,863  
% of Capital 1.45%  
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Nickel Futures LN March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 6  
Unrealized Gain (Loss) on Open Commodity Contracts (10,566)  
% of Capital (0.48%)  
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Aluminum Futures LA March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   24
Unrealized Gain (Loss) on Open Commodity Contracts   45,163
% of Capital   1.71%
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Tin Futures LT August 2013 contracts, expiring August 2013 [Member]
    
Number of Contracts   2
Unrealized Gain (Loss) on Open Commodity Contracts   10
% of Capital   0.00%
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Lead Futures LL February 2013 contracts, expiring February 2013 [Member]
    
Number of Contracts   3
Unrealized Gain (Loss) on Open Commodity Contracts   1,981
% of Capital   0.07%
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Tin Futures LT January 2013 contracts, expiring January 2013 [Member]
    
Number of Contracts   3
Unrealized Gain (Loss) on Open Commodity Contracts   42,880
% of Capital   1.62%
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Zinc Futures LX June 2014 contracts, expiring June 2014 [Member]
    
Number of Contracts 5  
Unrealized Gain (Loss) on Open Commodity Contracts (3,181)  
% of Capital (0.15%)  
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Aluminum Futures LA January 2015 contracts, expiring January 2015 [Member]
    
Number of Contracts 6  
Unrealized Gain (Loss) on Open Commodity Contracts (1,844)  
% of Capital (0.08%)  
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Nickel Futures LN February 2013 contracts, expiring February 2013 [Member]
    
Number of Contracts   4
Unrealized Gain (Loss) on Open Commodity Contracts   9,768
% of Capital   0.37%
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | Foreign [Member] | LME Zinc Futures LX June 2013 contracts, expiring June 2013 [Member]
    
Number of Contracts   7
Unrealized Gain (Loss) on Open Commodity Contracts   25,906
% of Capital   0.98%
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member]
    
Number of Contracts 15 14
Unrealized Gain (Loss) on Open Commodity Contracts (33,683) (31,335)
% of Capital (1.53%) (1.18%)
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | COMEX Copper Futures HG March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 6  
Unrealized Gain (Loss) on Open Commodity Contracts 16,812  
% of Capital 0.77%  
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | COMEX Copper Futures HG March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   6
Unrealized Gain (Loss) on Open Commodity Contracts   12,175
% of Capital   0.46%
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | NYMEX Platinum Futures PL April 2013 contracts, expiring April 2013 [Member]
    
Number of Contracts   2
Unrealized Gain (Loss) on Open Commodity Contracts   (2,900)
% of Capital   (0.11%)
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | COMEX Silver Futures SI March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 3  
Unrealized Gain (Loss) on Open Commodity Contracts (45,885)  
% of Capital (2.09%)  
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | NYMEX Palladium Futures PA March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 3  
Unrealized Gain (Loss) on Open Commodity Contracts (2,960)  
% of Capital (0.13%)  
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | COMEX Gold Futures GC April 2014 contracts, expiring April 2014 [Member]
    
Number of Contracts 3  
Unrealized Gain (Loss) on Open Commodity Contracts (1,650)  
% of Capital (0.08%)  
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | CME Palladium Futures PA March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   1
Unrealized Gain (Loss) on Open Commodity Contracts   275
% of Capital   0.01%
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | COMEX Gold Futures GC April 2013 contracts, expiring April 2013 [Member]
    
Number of Contracts   2
Unrealized Gain (Loss) on Open Commodity Contracts   3,250
% of Capital   0.13%
United States Metals Index Fund [Member] | Open Futures Contracts, Long [Member] | United States Contracts [Member] | COMEX Silver Futures SI May 2013 contracts, expiring May 2013 [Member]
    
Number of Contracts   3
Unrealized Gain (Loss) on Open Commodity Contracts   (44,135)
% of Capital   (1.67%)
United States Metals Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member]
    
Number of Contracts 38 [8] 27 [8]
Unrealized Gain (Loss) on Open Commodity Contracts 33,008 [8] (48,315) [8]
% of Capital 1.50% [8] (1.83%) [8]
United States Metals Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Tin Futures LT March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 3 [8]  
Unrealized Gain (Loss) on Open Commodity Contracts 10,236 [8]  
% of Capital 0.47% [8]  
United States Metals Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Lead Futures LL April 2014 contracts, expiring April 2014 [Member]
    
Number of Contracts 6 [8]  
Unrealized Gain (Loss) on Open Commodity Contracts (10,233) [8]  
% of Capital (0.47%) [8]  
United States Metals Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Aluminum Futures LA January 2014 contracts, expiring January 2014 [Member]
    
Number of Contracts 15 [8]  
Unrealized Gain (Loss) on Open Commodity Contracts 27,961 [8]  
% of Capital 1.27% [8]  
United States Metals Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Zinc Futures LX January 2014 contracts, expiring January 2014 [Member]
    
Number of Contracts 10 [8]  
Unrealized Gain (Loss) on Open Commodity Contracts (3,963) [8]  
% of Capital (0.18%) [8]  
United States Metals Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Nickel Futures LN March 2014 contracts, expiring March 2014 [Member]
    
Number of Contracts 4 [8]  
Unrealized Gain (Loss) on Open Commodity Contracts 9,007 [8]  
% of Capital 0.41% [8]  
United States Metals Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Aluminum Futures LA March 2013 contracts, expiring March 2013 [Member]
    
Number of Contracts   18 [8]
Unrealized Gain (Loss) on Open Commodity Contracts   (42,123) [8]
% of Capital   (1.59%) [8]
United States Metals Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Tin Futures LT January 2013 contracts, expiring January 2013 [Member]
    
Number of Contracts   3 [8]
Unrealized Gain (Loss) on Open Commodity Contracts   (7,951) [8]
% of Capital   (0.30%) [8]
United States Metals Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Nickel Futures LN February 2013 contracts, expiring February 2013 [Member]
    
Number of Contracts   2 [8]
Unrealized Gain (Loss) on Open Commodity Contracts   615 [8]
% of Capital   0.02% [8]
United States Metals Index Fund [Member] | Open Futures Contracts, Short [Member] | Foreign [Member] | LME Zinc Futures LX June 2013 contracts, expiring June 2013 [Member]
    
Number of Contracts   4 [8]
Unrealized Gain (Loss) on Open Commodity Contracts   1,144 [8]
% of Capital   0.04% [8]
United States Metals Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member]
    
Market Value 1,199,914  
% of Capital 54.61%  
United States Metals Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.05%, 1/09/2014 [Member]
    
Principal Amount 600,000  
Market Value 599,992  
% of Capital 27.31%  
United States Metals Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.06%, 1/09/2014 [Member]
    
Principal Amount 100,000  
Market Value 99,999  
% of Capital 4.55%  
United States Metals Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.05%, 3/27/2014 [Member]
    
Principal Amount 200,000  
Market Value 199,979  
% of Capital 9.10%  
United States Metals Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.06%, 4/17/2014 [Member]
    
Principal Amount 200,000  
Market Value 199,966  
% of Capital 9.10%  
United States Metals Index Fund [Member] | Cash Equivalents [Member] | US Treasury Securities [Member] | U.S.Treasury Bills 0.07%, 4/24/2014 [Member]
    
Principal Amount 100,000  
Market Value $ 99,978  
% of Capital 4.55%  
[1] Collateral amounted to $20,013,191 on open futures contracts.
[2] All short contracts are offset by the same number of Futures Contracts in the corresponding long positions and are acquired solely for the purpose of reducing a long position (e.g., due to a redemption or to reflect a rebalancing of the SDCI).
[3] Collateral amounted to $428,041 on open futures contracts.
[4] Collateral amounted to $230,081 on open futures contracts.
[5] Collateral amounted to $673,421 on open futures contracts.
[6] Collateral amounted to $329,598 on open futures contracts.
[7] Collateral amounted to $462,075 on open futures contracts.
[8] All short contracts are offset by the same number of Futures Contracts in the corresponding long positions and are acquired solely for the purpose of reducing a long position (e.g., due to a redemption or to reflect a rebalancing of the SDMI).