United States Copper Index Fund (CPER) 10-Q12 Nov 132013 Q3 Quarterly reportFinancial data

Company Profile

Document_And_Entity_Informatio

Document And Entity Information	9 Months Ended
Document And Entity Information	Sep. 30, 2013
Document Information [Line Items]	'
Document Type	'10-Q
Amendment Flag	'false
Document Period End Date	30-Sep-13
Document Fiscal Year Focus	'2013
Document Fiscal Period Focus	'Q3
Trading Symbol	'USCI
Entity Common Stock, Shares Outstanding	0
Entity Registrant Name	'United States Commodity Index Funds Trust
Entity Central Index Key	'0001479247
Current Fiscal Year End Date	'--12-31
Entity Filer Category	'Accelerated Filer

Condensed_Statements_of_Financ

Condensed Statements of Financial Condition (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012
Condensed Statements of Financial Condition (USD $)	Sep. 30, 2013	Dec. 31, 2012	United States Commodity Index Fund [Member]	United States Commodity Index Fund [Member]	United States Copper Index Fund [Member]	United States Copper Index Fund [Member]	United States Agriculture Index Fund [Member]	United States Agriculture Index Fund [Member]	United States Metals Index Fund [Member]	United States Metals Index Fund [Member]
Assets	'	'	'	'	'	'	'	'	'	'
Cash and cash equivalents (Notes 2 and 6)	$482,191,119	$437,046,560	$476,266,020	$430,800,077	$2,022,145	$2,109,061	$2,021,071	$2,000,438	$1,881,883	$2,136,984
Equity in Newedge trading accounts:	'	'	'	'	'	'	'	'	'	'
Cash and cash equivalents	72,177,131	61,899,628	71,147,145	60,319,627	218,185	432,529	386,533	679,407	425,268	468,065
Unrealized loss on open commodity futures contracts	754,074	-5,287,422	792,122	-5,220,900	25,075	6,575	-35,928	-119,155	-27,195	46,058
Receivable for units sold	0	2,922,886	0	2,922,886	'	'	'	'	'	'
Receivable from Sponsor (Note 4)	221,485	232,531	'	'	67,171	96,364	77,136	76,851	77,178	59,316
Interest receivable	1,343	531	1,261	474	25	18	46	32	11	7
Other assets	19,204	4,686	18,931	4,657	91	29	89	0	93	0
Total assets	555,364,356	496,819,400	548,225,479	488,826,821	2,332,692	2,644,576	2,448,947	2,637,573	2,357,238	2,710,430
Liabilities and Capital	'	'	'	'	'	'	'	'	'	'
Management fees payable (Note 4)	426,538	398,979	422,371	394,233	1,189	1,393	1,562	1,772	1,416	1,581
Professional fees payable	464,961	554,124	235,247	312,296	69,772	100,193	79,830	80,030	80,112	61,605
Brokerage commissions payable	22,815	22,815	22,815	22,815	'	'	'	'	'	'
Other liabilities	15,971	11,940	15,745	11,750	49	44	85	79	92	67
Total liabilities	930,285	987,858	696,178	741,094	71,010	101,630	81,477	81,881	81,620	63,253
Capital	'	'	'	'	'	'	'	'	'	'
Sponsor	0	0	0	0	0	0	0	0	0	0
Unitholders	554,434,071	495,831,542	547,529,301	488,085,727	2,261,682	2,542,946	2,367,470	2,555,692	2,275,618	2,647,177
Total Capital	554,434,071	495,831,542	547,529,301	488,085,727	2,261,682	2,542,946	2,367,470	2,555,692	2,275,618	2,647,177
Total liabilities and capital	$555,364,356	$496,819,400	$548,225,479	$488,826,821	$2,332,692	$2,644,576	$2,448,947	$2,637,573	$2,357,238	$2,710,430
Units outstanding	10,050,000	8,650,000	9,750,000	8,350,000	100,000	100,000	100,000	100,000	100,000	100,000
Net asset value per unit	'	'	$56.16	$58.45	$22.62	$25.43	$23.67	$25.56	$22.76	$26.47
Market value per unit	'	'	$55.97	$58.63	$22.44	$25.01	$23.33	$25.59	$22.05	$31.07

Condensed_Schedule_of_Investme

Condensed Schedule of Investments (USD $)	Sep. 30, 2013
Condensed Schedule of Investments (USD $)	Contract
United States Commodity Index Fund [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	14,844	[1]
Unrealized Gain (Loss) on Open Commodity Contracts	$792,122	[1]
% of Capital	0.14%	[1]
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	5,806
Unrealized Gain (Loss) on Open Commodity Contracts	4,942,442
% of Capital	0.90%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Zinc Futures LX October 2013 contracts, expiring October 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	748
Unrealized Gain (Loss) on Open Commodity Contracts	-3,887,544
% of Capital	-0.71%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Tin Futures LT November 2013 contracts, expiring November 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	354
Unrealized Gain (Loss) on Open Commodity Contracts	728,603
% of Capital	0.13%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Cotton #2 Futures CT December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	922
Unrealized Gain (Loss) on Open Commodity Contracts	1,867,330
% 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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	387
Unrealized Gain (Loss) on Open Commodity Contracts	6,359,425
% of Capital	1.16%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Lead Futures LL April 2014 contracts, expiring April 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	711
Unrealized Gain (Loss) on Open Commodity Contracts	-1,437,788
% of Capital	-0.26%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Zinc Futures LX April 2014 contracts, expiring April 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	790
Unrealized Gain (Loss) on Open Commodity Contracts	-627,394
% of Capital	-0.11%
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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	1,515
Unrealized Gain (Loss) on Open Commodity Contracts	456,800
% of Capital	0.08%
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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	379
Unrealized Gain (Loss) on Open Commodity Contracts	1,483,010
% of Capital	0.27%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	6,385
Unrealized Gain (Loss) on Open Commodity Contracts	2,467,721
% of Capital	0.45%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Feeder Cattle Futures FC November 2013 contracts, expiring November 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	476
Unrealized Gain (Loss) on Open Commodity Contracts	1,362,650
% of Capital	0.25%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Soybean Meal Futures SM December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	936
Unrealized Gain (Loss) on Open Commodity Contracts	3,158,150
% of Capital	0.58%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Lean Hogs Futures LH December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	1,102
Unrealized Gain (Loss) on Open Commodity Contracts	-501,330
% of Capital	-0.09%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| COMEX Copper Futures HG December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	477
Unrealized Gain (Loss) on Open Commodity Contracts	180,388
% of Capital	0.03%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| NYMEX RBOB Gasoline Futures RB December 2013 contracts, expiring November 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	353
Unrealized Gain (Loss) on Open Commodity Contracts	-395,359
% of Capital	-0.07%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| NYMEX Platinum Futures PL January 2014 contracts, expiring January 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	545
Unrealized Gain (Loss) on Open Commodity Contracts	-3,090,710
% of Capital	-0.57%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Live Cattle Futures LC February 2014 contracts, expiring February 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	734
Unrealized Gain (Loss) on Open Commodity Contracts	99,260
% of Capital	0.02%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| NYMEX Natural Gas Futures NG April 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	1,043
Unrealized Gain (Loss) on Open Commodity Contracts	-751,650
% of Capital	-0.14%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| NYMEX WTI Crude Oil Futures CL April 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	398
Unrealized Gain (Loss) on Open Commodity Contracts	2,393,470
% of Capital	0.44%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| NYMEX Heating Oil Futures HO June 2014 contracts, expiring May 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	321
Unrealized Gain (Loss) on Open Commodity Contracts	12,852
% of Capital	0.00%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	2,653	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	-6,618,041	[2]
% of Capital	-1.21%	[2]
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Zinc Futures LX October 2013 contracts, expiring October 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	748	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	559,456	[2]
% of Capital	0.10%	[2]
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Tin Futures LT November 2013 contracts, expiring November 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	354	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	-6,293,027	[2]
% of Capital	-1.15%	[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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	50	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	-205,241	[2]
% of Capital	-0.04%	[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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	711	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	-376,762	[2]
% of Capital	-0.07%	[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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	790	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	-302,467	[2]
% of Capital	-0.05%	[2]
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member]	'
Offsetting Liabilities [Line Items]	'
Market Value	345,168,420
% of Capital	63.04%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 10/10/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	20,000,000
Market Value	19,999,794
% of Capital	3.65%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 10/10/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	20,000,000
Market Value	19,999,794
% of Capital	3.65%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.02%,10/17/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	40,000,000
Market Value	39,999,556
% of Capital	7.31%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 10/17/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	20,000,000
Market Value	19,999,778
% of Capital	3.65%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.01%, 10/24/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	20,000,000
Market Value	19,999,808
% of Capital	3.65%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 11/07/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	20,000,000
Market Value	19,999,239
% of Capital	3.65%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.02%, 11/21/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	20,000,000
Market Value	19,999,386
% of Capital	3.65%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.03%, 11/21/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	10,000,000
Market Value	9,999,693
% of Capital	1.83%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 12/26/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	30,000,000
Market Value	29,996,113
% of Capital	5.48%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 1/09/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	55,000,000
Market Value	54,991,479
% of Capital	10.05%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 1/09/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	20,000,000
Market Value	19,996,902
% of Capital	3.65%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 1/30/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	20,000,000
Market Value	19,997,017
% of Capital	3.65%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 3/06/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	20,200,000
Market Value	20,196,499
% of Capital	3.69%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/27/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	30,000,000
Market Value	29,993,362
% of Capital	5.48%
United States Copper Index Fund [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	27	[3]
Unrealized Gain (Loss) on Open Commodity Contracts	25,075	[3]
% of Capital	1.11%	[3]
United States Copper Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| COMEX Copper Futures HG November 2013 contracts, expiring November 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	7
Unrealized Gain (Loss) on Open Commodity Contracts	-10,163
% of Capital	-0.45%
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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	7
Unrealized Gain (Loss) on Open Commodity Contracts	-9,825
% of Capital	-0.43%
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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	13
Unrealized Gain (Loss) on Open Commodity Contracts	45,063
% of Capital	1.99%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member]	'
Offsetting Liabilities [Line Items]	'
Market Value	1,299,865
% of Capital	57.47%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 10/10/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	250,000
Market Value	249,998
% of Capital	11.05%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.02%,10/17/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	300,000
Market Value	299,997
% of Capital	13.27%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 12/26/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	50,000
Market Value	49,996
% of Capital	2.21%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.03%, 12/26/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	100,000
Market Value	99,991
% of Capital	4.42%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S. Treasury Bills 0.06%, 1/09/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	100,000
Market Value	99,983
% of Capital	4.42%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/06/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	400,000
Market Value	399,922
% of Capital	17.68%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/27/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	100,000
Market Value	99,978
% of Capital	4.42%
United States Agriculture Index Fund [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	69	[4]
Unrealized Gain (Loss) on Open Commodity Contracts	-35,928	[4]
% of Capital	-1.52%	[4]
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	29
Unrealized Gain (Loss) on Open Commodity Contracts	26,546
% of Capital	1.12%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Cocoa Futures CC December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	8
Unrealized Gain (Loss) on Open Commodity Contracts	18,400
% of Capital	0.78%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Coffee-C Futures KC December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	4
Unrealized Gain (Loss) on Open Commodity Contracts	-14,212
% of Capital	-0.60%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Cotton #2 Futures CT December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	4
Unrealized Gain (Loss) on Open Commodity Contracts	8,325
% of Capital	0.35%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Canola Futures RS March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	3
Unrealized Gain (Loss) on Open Commodity Contracts	-113
% of Capital	-0.01%
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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	10
Unrealized Gain (Loss) on Open Commodity Contracts	14,146
% of Capital	0.60%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	40
Unrealized Gain (Loss) on Open Commodity Contracts	-62,474
% of Capital	-2.64%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Lean Hogs Futures LH December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	6
Unrealized Gain (Loss) on Open Commodity Contracts	-3,340
% of Capital	-0.14%
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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	11
Unrealized Gain (Loss) on Open Commodity Contracts	-58,100
% of Capital	-2.45%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Soybean Meal Futures SM December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	4
Unrealized Gain (Loss) on Open Commodity Contracts	-10,530
% of Capital	-0.44%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Live Cattle Futures LC December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	6
Unrealized Gain (Loss) on Open Commodity Contracts	6,900
% of Capital	0.29%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| KCBOT Hard Red Winter Wheat Futures KW December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	1
Unrealized Gain (Loss) on Open Commodity Contracts	1,450
% of Capital	0.06%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Feeder Cattle Futures FC January 2014 contracts, expiring January 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	2
Unrealized Gain (Loss) on Open Commodity Contracts	6,162
% of Capital	0.26%
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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	1
Unrealized Gain (Loss) on Open Commodity Contracts	-2,016
% of Capital	-0.09%
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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	4
Unrealized Gain (Loss) on Open Commodity Contracts	1,850
% of Capital	0.08%
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]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	5
Unrealized Gain (Loss) on Open Commodity Contracts	-4,850
% of Capital	-0.21%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member]	'
Offsetting Liabilities [Line Items]	'
Market Value	1,249,883
% of Capital	52.79%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 10/10/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	100,000
Market Value	99,999
% of Capital	4.22%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.02%,10/17/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	400,000
Market Value	399,996
% of Capital	16.89%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.03%, 11/21/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	150,000
Market Value	149,993
% of Capital	6.33%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 12/26/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	200,000
Market Value	199,978
% of Capital	8.45%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/06/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	200,000
Market Value	199,961
% of Capital	8.45%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/27/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	200,000
Market Value	199,956
% of Capital	8.45%
United States Metals Index Fund [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	59	[5]
Unrealized Gain (Loss) on Open Commodity Contracts	-27,195	[5]
% of Capital	-1.20%	[5]
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	29
Unrealized Gain (Loss) on Open Commodity Contracts	-14,582
% of Capital	-0.64%
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Tin Futures LT March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	2
Unrealized Gain (Loss) on Open Commodity Contracts	26,695
% of Capital	1.17%
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Lead Futures LL April 2014 contracts, expiring April 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	4
Unrealized Gain (Loss) on Open Commodity Contracts	-8,481
% of Capital	-0.37%
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Aluminum Futures LA January 2014 contracts, expiring January 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	13
Unrealized Gain (Loss) on Open Commodity Contracts	-35,588
% of Capital	-1.56%
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Zinc Futures LX January 2014 contracts, expiring January 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	6
Unrealized Gain (Loss) on Open Commodity Contracts	1,163
% of Capital	0.05%
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Nickel Futures LN March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	4
Unrealized Gain (Loss) on Open Commodity Contracts	1,629
% of Capital	0.07%
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	15
Unrealized Gain (Loss) on Open Commodity Contracts	-14,453
% of Capital	-0.64%
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| COMEX Copper Futures HG December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	6
Unrealized Gain (Loss) on Open Commodity Contracts	-8,363
% of Capital	-0.37%
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| COMEX Gold Futures GC December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	3
Unrealized Gain (Loss) on Open Commodity Contracts	-24,860
% of Capital	-1.09%
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| COMEX Silver Futures SI December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	4
Unrealized Gain (Loss) on Open Commodity Contracts	19,540
% of Capital	0.86%
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| NYMEX Palladium Futures PA December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	2
Unrealized Gain (Loss) on Open Commodity Contracts	-770
% of Capital	-0.04%
United States Metals Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	15	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	1,840	[2]
% of Capital	0.08%	[2]
United States Metals Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Lead Futures LL April 2014 contracts, expiring April 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	3	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	-648	[2]
% of Capital	-0.03%	[2]
United States Metals Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Aluminum Futures LA January 2014 contracts, expiring January 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	7	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	4,491	[2]
% of Capital	0.20%	[2]
United States Metals Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Zinc Futures LX January 2014 contracts, expiring January 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	2	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	272	[2]
% of Capital	0.01%	[2]
United States Metals Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Nickel Futures LN March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	2	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	-2,294	[2]
% of Capital	-0.10%	[2]
United States Metals Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Tin Futures LN March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Number of Contracts	1	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	19	[2]
% of Capital	0.00%	[2]
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member]	'
Offsetting Liabilities [Line Items]	'
Market Value	1,549,823
% of Capital	68.11%
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 10/03/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	200,000
Market Value	199,999
% of Capital	8.79%
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.02%,10/17/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	200,000
Market Value	199,999
% of Capital	8.79%
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.03%, 11/21/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	100,000
Market Value	99,995
% of Capital	4.40%
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 12/26/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	150,000
Market Value	149,981
% of Capital	6.59%
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 1/09/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	600,000
Market Value	599,908
% of Capital	26.36%
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 1/09/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	100,000
Market Value	99,985
% of Capital	4.39%
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/27/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Principal Amount	200,000
Market Value	$199,956
% of Capital	8.79%

[1]	Collateral amounted to $70,396,727 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 Commodity Index).
[3]	Collateral amounted to $216,693 on open futures contracts.
[4]	Collateral amounted to $383,552 on open futures contracts
[5]	Collateral amounted to $422,267 on open futures contracts.

Condensed_Schedule_of_Investme1

Condensed Schedule of Investments (Parenthetical) (USD $)	9 Months Ended
Condensed Schedule of Investments (Parenthetical) (USD $)	Sep. 30, 2013
United States Commodity Index Fund [Member] \| United States [Member] \| CME Feeder Cattle Futures FC November 2013 contracts, expiring November 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'November 2013
United States Commodity Index Fund [Member] \| United States [Member] \| CBOT Soybean Meal Futures SM December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Commodity Index Fund [Member] \| United States [Member] \| CME Lean Hogs Futures LH December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Commodity Index Fund [Member] \| United States [Member] \| COMEX Copper Futures HG December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Commodity Index Fund [Member] \| United States [Member] \| NYMEX RBOB Gasoline Futures RB December 2013 contracts, expiring November 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'November 2013
United States Commodity Index Fund [Member] \| United States [Member] \| NYMEX Platinum Futures PL January 2014 contracts, expiring January 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'January 2014
United States Commodity Index Fund [Member] \| United States [Member] \| CME Live Cattle Futures LC February 2014 contracts, expiring February 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'February 2014
United States Commodity Index Fund [Member] \| United States [Member] \| NYMEX Natural Gas Futures NG April 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'March 2014
United States Commodity Index Fund [Member] \| United States [Member] \| NYMEX WTI Crude Oil Futures CL April 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'March 2014
United States Commodity Index Fund [Member] \| United States [Member] \| NYMEX Heating Oil Futures HO June 2014 contracts, expiring May 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'May 2014
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Zinc Futures LX October 2013 contracts, expiring October 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'October 2013
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Tin Futures LT November 2013 contracts, expiring November 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'November 2013
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Cotton #2 Futures CT December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Tin Futures LT March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'March 2014
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Lead Futures LL April 2014 contracts, expiring April 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'April 2014
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Zinc Futures LX April 2014 contracts, expiring April 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'April 2014
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]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'May 2014
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]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'May 2014
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Zinc Futures LX October 2013 contracts, expiring October 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'October 2013
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Tin Futures LT November 2013 contracts, expiring November 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'November 2013
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Tin Futures LT March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'March 2014
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Lead Futures LL April 2014 contracts, expiring April 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'April 2014
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Zinc Futures LX April 2014 contracts, expiring April 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'April 2014
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 10/10/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.04%
Expiration date	'10/10/2013
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 10/10/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'10/10/2013
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.02%, 10/17/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.02%
Expiration date	'10/17/2013
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 10/17/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.04%
Expiration date	'10/17/2013
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.01%, 10/24/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.01%
Expiration date	'10/24/2013
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 11/07/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.04%
Expiration date	'11/07/2013
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.02%, 11/21/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.02%
Expiration date	'11/21/2013
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.03%, 11/21/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.03%
Expiration date	'11/21/2013
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 12/26/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'12/26/2013
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 1/09/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'1/09/2014
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 1/09/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.06%
Expiration date	'1/09/2014
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 1/30/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.04%
Expiration date	'1/30/2014
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 3/06/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.04%
Expiration date	'3/06/2014
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/27/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/27/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'3/27/2014
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| OpenFuturesContractsTotalMember [Member] \| US Treasury Securities [Member]	'
Offsetting Liabilities [Line Items]	'
Debt Instrument, Collateral Amount	70,396,727
United States Copper Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| COMEX Copper Futures HG November 2013 contracts, expiring November 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'November 2013
United States Copper Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| COMEX Copper Futures HG December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Copper Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| COMEX Copper Futures HG March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'March 2014
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member]	'
Offsetting Liabilities [Line Items]	'
Debt Instrument, Collateral Amount	216,693
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 10/10/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.04%
Expiration date	'10/10/2013
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.02%, 10/17/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.02%
Expiration date	'10/17/2013
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.03%, 12/26/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.03%
Expiration date	'12/26/2013
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 12/26/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'12/26/2013
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 1/09/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.06%
Expiration date	'1/09/2014
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/06/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'3/06/2014
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/27/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'3/27/2014
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Cocoa Futures CC December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Coffee-C Futures KC December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Cotton #2 Futures CT December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Canola Futures RS March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'March 2014
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]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'April 2014
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| CME Lean Hogs Futures LH December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| CBOT Corn Futures C December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| CBOT Soybean Meal Futures SM December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| CME Live Cattle Futures LC December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| KCBOT Hard Red Winter Wheat Futures KW December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| CME Feeder Cattle Futures FC January 2014 contracts, expiring January 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'January 2014
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| CBOT Soybean Oil Futures BO March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'March 2014
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| CBOT Wheat Futures W March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'March 2014
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| CBOT Soybean Futures S November 2013 contracts, expiring November 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'November 2014
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member]	'
Offsetting Liabilities [Line Items]	'
Debt Instrument, Collateral Amount	383,552
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.04%, 10/10/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.04%
Expiration date	'10/10/2013
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.02%, 10/17/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.02%
Expiration date	'10/17/2013
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.03%, 11/21/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.03%
Expiration date	'11/21/2013
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 12/26/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'12/26/2013
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/06/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'3/06/2014
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/27/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'3/27/2014
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Tin Futures LT March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'March 2014
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Lead Futures LL April 2014 contracts, expiring April 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'April 2014
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Aluminum Futures LA January 2014 contracts, expiring January 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'January 2014
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Zinc Futures LX January 2014 contracts, expiring January 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'January 2014
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Nickel Futures LN March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'March 2014
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| COMEX Copper Futures HG December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| COMEX Gold Futures GC December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Metals Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| COMEX Silver Futures SI December 2013 contracts, expiring December 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Metals Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Tin Futures LT March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'March 2014
United States Metals Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Lead Futures LL April 2014 contracts, expiring April 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'April 2014
United States Metals Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Zinc Futures LX April 2014 contracts, expiring April 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'January 2014
United States Metals Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Aluminum Futures LA January 2014 contracts, expiring January 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'January 2014
United States Metals Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Nickel Futures LN March 2014 contracts, expiring March 2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'March 2014
United States Metals Index Fund [Member] \| Open Futures Contracts, Short [Member] \| United States [Member] \| NYMEX Palladium Futures PA June 2013 contracts, expiring June 2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Expiration date	'December 2013
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member]	'
Offsetting Liabilities [Line Items]	'
Debt Instrument, Collateral Amount	422,267
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 10/03/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'10/03/2013
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.02%, 10/17/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.02%
Expiration date	'10/17/2013
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.03%, 11/21/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.03%
Expiration date	'11/21/2013
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 12/26/2013 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'12/26/2013
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 1/09/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'1/09/2014
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 1/09/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.06%
Expiration date	'1/09/2014
United States Metals Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 3/27/2014 [Member]	'
Offsetting Liabilities [Line Items]	'
Interest rate	0.05%
Expiration date	'3/27/2014

Condensed_Statements_of_Operat

Condensed Statements of Operations (USD $)	3 Months Ended				9 Months Ended
Condensed Statements of Operations (USD $)	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Gain (loss) on trading of commodity futures contracts:	'		'		'		'
Realized gain (loss) on closed positions	($2,505,308)		$21,279,445		($23,861,351)		($11,794,178)
Change in unrealized gain (loss) on open positions	28,531,435		6,877,274		6,041,496		31,489,301
Realized gain (loss) on foreign currency transactions	16		239		162		209
Realized gain on short-term investments	3		-7		4		-7
Change in unrealized gain (loss) on foreign currency translations	-11		93		93		106
Interest income	55,365		84,195		209,545		180,311
Other income	4,500		9,250		11,850		14,150
Total income (loss)	26,086,000		28,250,489		-17,598,201		19,889,892
Expenses	'		'		'		'
Management fees (Note 4)	1,256,009		1,058,309		3,663,785		2,947,977
Professional fees	162,246		251,083		594,523		555,065
Brokerage commissions	82,737		90,010		286,855		227,355
Other expenses	28,347		18,183		77,976		51,608
Total expenses	1,529,339		1,417,585		4,623,139		3,782,005
Expense waiver (Note 4)	-53,332		-75,671		-221,484		-140,801
Net expenses	1,476,007		1,341,914		4,401,655		3,641,204
Net income (loss)	24,609,993		26,908,575		-21,999,856		16,248,688
United States Commodity Index Fund [Member]	'		'		'		'
Gain (loss) on trading of commodity futures contracts:	'		'		'		'
Realized gain (loss) on closed positions	-2,442,019		20,615,262		-23,085,330		-12,231,495
Change in unrealized gain (loss) on open positions	28,036,614		6,757,910		6,013,022		31,016,267
Realized gain (loss) on foreign currency transactions	-45		0		324		0
Change in unrealized gain (loss) on foreign currency translations	-11		-170		207		-130
Interest income	54,656		82,589		206,472		177,504
Other income	3,150		4,200		10,500		8,750
Total income (loss)	25,652,345		27,459,791		-16,854,805		18,970,896
Expenses	'		'		'		'
Management fees (Note 4)	1,242,536		1,042,577		3,624,369		2,914,069
Professional fees	106,094		173,144		364,809		408,917
Brokerage commissions	81,812		88,340		284,139		224,208
Other expenses	27,944		17,911		76,913		51,053
Total expenses	1,458,386		1,321,972		4,350,230		3,598,247
Expense waiver (Note 4)	0		0		0		0
Net expenses	1,458,386		1,321,972		4,350,230		3,598,247
Net income (loss)	24,193,959		26,137,819		-21,205,035		15,372,649
Net income (loss) per unit	$2.65		$3.84		($2.29)		$2.88
Net loss per weighted average unit	$2.60		$3.65		($2.35)		$2.27
Weighted average units outstanding	9,308,696		7,161,957		9,040,476		6,781,022
United States Copper Index Fund [Member]	'		'		'		'
Gain (loss) on trading of commodity futures contracts:	'		'		'		'
Realized gain (loss) on closed positions	-60,425		19,112		-285,950		-63,313
Change in unrealized gain (loss) on open positions	233,325		171,925		18,500		278,838
Interest income	214		426		990		1,093
Other income	0		1,350		0		1,350
Total income (loss)	173,114		192,813		-266,460		217,968
Expenses	'		'		'		'
Management fees (Note 4)	3,609		4,096		11,294		15,712
Professional fees	20,014		24,257		69,772		67,441
Brokerage commissions	149		278		549		597
Other expenses	125		111		360		309
Total expenses	23,897		28,742		81,975		84,059
Expense waiver (Note 4)	-19,181		-23,656		-67,171		-64,905
Net expenses	4,716		5,086		14,804		19,154
Net income (loss)	168,398		187,727		-281,264		198,814
Net income (loss) per unit	$1.69		$1.72		($2.81)		$1.83
Net loss per weighted average unit	$1.68		$1.85		($2.81)		$1.98
Weighted average units outstanding	100,000		101,630		100,000		100,549
United States Agriculture Index Fund [Member]	'		'		'		'
Gain (loss) on trading of commodity futures contracts:	'		'		'		'
Realized gain (loss) on closed positions	12,807	[1]	482,644	[1]	-253,247	[1]	368,209	[1]
Change in unrealized gain (loss) on open positions	29,817	[1]	-227,945	[1]	83,227	[1]	18,483	[1]
Realized gain (loss) on foreign currency transactions	61	[1]	239	[1]	-165	[1]	209	[1]
Realized gain on short-term investments	2	[1]	-2	[1]	2	[1]	-2	[1]
Change in unrealized gain (loss) on foreign currency translations	0	[1]	264	[1]	-116	[1]	237	[1]
Interest income	217	[1]	547	[1]	1,036	[1]	1,014	[1]
Other income	0	[1]	2,350	[1]	0	[1]	2,700	[1]
Total income (loss)	42,904	[1]	258,097	[1]	-169,263	[1]	390,850	[1]
Expenses	'		'		'		'
Management fees (Note 4)	4,730	[1]	6,151	[1]	14,402	[1]	12,155	[1]
Professional fees	17,928	[1]	26,841	[1]	79,830	[1]	48,566	[1]
Brokerage commissions	510	[1]	1,098	[1]	1,524	[1]	2,074	[1]
Other expenses	128	[1]	80	[1]	338	[1]	156	[1]
Total expenses	23,296	[1]	34,170	[1]	96,094	[1]	62,951	[1]
Expense waiver (Note 4)	-17,041	[1]	-26,019	[1]	-77,135	[1]	-46,719	[1]
Net expenses	6,255	[1]	8,151	[1]	18,959	[1]	16,232	[1]
Net income (loss)	36,649	[1]	249,946	[1]	-188,222	[1]	374,618	[1]
Net income (loss) per unit	$0.36	[1]	$1.85	[1]	($1.89)	[1]	$2.38	[1]
Net loss per weighted average unit	$0.37	[1]	$2.25	[1]	($1.88)	[1]	$3.11	[1]
Weighted average units outstanding	100,000	[1]	110,870	[1]	100,000	[1]	120,486	[1]
United States Metals Index Fund [Member]	'		'		'		'
Gain (loss) on trading of commodity futures contracts:	'		'		'		'
Realized gain (loss) on closed positions	-15,671	[2]	162,427	[2]	-236,824	[2]	132,421	[2]
Change in unrealized gain (loss) on open positions	231,679	[2]	175,384	[2]	-73,253	[2]	175,713	[2]
Realized gain (loss) on foreign currency transactions	0	[2]	0	[2]	3	[2]	0	[2]
Realized gain on short-term investments	1	[2]	-5	[2]	2	[2]	-5	[2]
Change in unrealized gain (loss) on foreign currency translations	0	[2]	-1	[2]	2	[2]	-1	[2]
Interest income	278	[2]	633	[2]	1,047	[2]	700	[2]
Other income	1,350	[2]	1,350	[2]	1,350	[2]	1,350	[2]
Total income (loss)	217,637	[2]	339,788	[2]	-307,673	[2]	310,178	[2]
Expenses	'		'		'		'
Management fees (Note 4)	5,134	[2]	5,485	[2]	13,720	[2]	6,041	[2]
Professional fees	18,210	[2]	26,841	[2]	80,112	[2]	30,141	[2]
Brokerage commissions	266	[2]	294	[2]	643	[2]	476	[2]
Other expenses	150	[2]	81	[2]	365	[2]	90	[2]
Total expenses	23,760	[2]	32,701	[2]	94,840	[2]	36,748	[2]
Expense waiver (Note 4)	-17,110	[2]	-25,996	[2]	-77,178	[2]	-29,177	[2]
Net expenses	6,650	[2]	6,705	[2]	17,662	[2]	7,571	[2]
Net income (loss)	$210,987	[2]	$333,083	[2]	($325,335)	[2]	$302,607	[2]
Net income (loss) per unit	$1.65	[2]	$2.97	[2]	($3.71)	[2]	$2.67	[2]
Net loss per weighted average unit	$1.62	[2]	$2.69	[2]	($2.96)	[2]	$2.50	[2]
Weighted average units outstanding	129,891	[2]	123,939	[2]	110,073	[2]	121,181	[2]

[1]	The commencement of operations of the United States Agriculture Index Fund was April 13, 2012.
[2]	The commencement of operations of the United States Metals Index Fund was June 19, 2012.

Condensed_Statement_of_Changes

Condensed Statement of Changes in Capital (USD $)	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013		Sep. 30, 2013		Sep. 30, 2013		Sep. 30, 2013		Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013
			United States Commodity Index Fund [Member]	United States Commodity Index Fund [Member]	United States Copper Index Fund [Member]	United States Copper Index Fund [Member]	United States Agriculture Index Fund [Member]		United States Agriculture Index Fund [Member]		United States Metals Index Fund [Member]		United States Metals Index Fund [Member]		Sponsor [Member]	Sponsor [Member]	Sponsor [Member]	Sponsor [Member]	Sponsor [Member]	Unitholders [Member]	Unitholders [Member]	Unitholders [Member]	Unitholders [Member]	Unitholders [Member]
																United States Commodity Index Fund [Member]	United States Copper Index Fund [Member]	United States Agriculture Index Fund [Member]	United States Metals Index Fund [Member]		United States Commodity Index Fund [Member]	United States Copper Index Fund [Member]	United States Agriculture Index Fund [Member]	United States Metals Index Fund [Member]
Offsetting Liabilities [Line Items]	'	'	'	'	'	'	'		'		'		'		'	'	'	'	'	'	'	'	'	'
Balances	'	$495,831,542	'	$488,085,727	'	$2,542,946	'		$2,555,692		'		$2,647,177		$0	$0	$0	$0	$0	$495,831,542	$488,085,727	$2,542,946	$2,555,692	$2,647,177
Additions	'	101,140,170	'	100,050,394	'	0	'		0		'		1,089,776		0	0	0	0	0	101,140,170	100,050,394	0	0	1,089,776
Redemptions	'	-20,537,785	'	-19,401,785	'	0	'		0		'		-1,136,000		0	0	0	0	0	-20,537,785	-19,401,785	0	0	-1,136,000
Net loss	24,609,993	-21,999,856	24,193,959	-21,205,035	168,398	-281,264	36,649	[1]	-188,222	[1]	210,987	[2]	-325,335	[2]	0	0	0	0	0	-21,999,856	-21,205,035	-281,264	-188,222	-325,335
Balances	$554,434,071	$554,434,071	$547,529,301	$547,529,301	$2,261,682	$2,261,682	$2,367,470		$2,367,470		$2,275,618		$2,275,618		$0	$0	$0	$0	$0	$554,434,071	$547,529,301	$2,261,682	$2,367,470	$2,275,618
Units Outstanding	'	8,650,000	'	8,350,000	'	100,000	'		100,000		'		100,000		0	0	0	0	0	8,650,000	8,350,000	100,000	100,000	100,000
Additions	'	1,800,000	'	1,750,000	'	0	'		0		'		50,000		0	0	0	0	0	1,800,000	1,750,000	0	0	50,000
Redemptions	'	-400,000	'	-350,000	'	0	'		0		'		-50,000		0	0	0	0	0	-400,000	-350,000	0	0	-50,000
Units Outstanding	10,050,000	10,050,000	9,750,000	9,750,000	100,000	100,000	100,000		100,000		100,000		100,000		0	0	0	0	0	10,050,000	9,750,000	100,000	100,000	100,000
Net Asset Value Per Unit:	'	'	'	'	'	'	'		'		'		'		'	'	'	'	'	'	'	'	'	'
Net asset value, beginning of period	'	'	'	$58.45	'	$25.43	'		$25.56		'		$26.47		'	'	'	'	'	'	'	'	'	'
Net asset value, end of period	'	'	$56.16	$56.16	$22.62	$22.62	$23.67		$23.67		$22.76		$22.76		'	'	'	'	'	'	'	'	'	'

[1]	The commencement of operations of the United States Agriculture Index Fund was April 13, 2012.
[2]	The commencement of operations of the United States Metals Index Fund was June 19, 2012.

Condensed_Statements_of_Cash_F

Condensed Statements of Cash Flows (USD $)	9 Months Ended
Condensed Statements of Cash Flows (USD $)	Sep. 30, 2013		Sep. 30, 2012
Cash Flows from Operating Activities:	'		'
Net income (loss)	($21,999,856)		$16,248,688
Adjustments to reconcile net income (loss) to net cash used in operating activities:	'		'
(Increase) decrease in commodity futures trading account - cash and cash equivalents	-10,277,503		33,795
Unrealized gain on open futures contracts	-6,041,496		-31,489,301
(Increase) decrease in receivable from Sponsor	11,045		-128,349
Increase in interest receivable	-812		-399
Increase in other assets	-14,517		-8,360
Increase (decrease) in management fees payable	27,559		31,451
Increase (decrease) in professional fees payable	-89,163		149,887
Decrease in brokerage commissions payable	0		-3,380
Increase (decrease) in other liabilities	4,031		-8,081
Net cash used in operating activities	-38,380,712		-15,174,049
Cash Flows from Financing Activities:	'		'
Addition of units	104,063,056		127,567,106
Redemption of units	-20,537,785		-22,740,216
Net cash provided by financing activities	83,525,271		104,826,890
Net Increase in Cash and Cash Equivalents	45,144,559		89,652,841
Cash and Cash Equivalents, beginning of period	437,046,560		312,608,059
Cash and Cash Equivalents, end of period	482,191,119		402,260,900
United States Commodity Index Fund [Member]	'		'
Cash Flows from Operating Activities:	'		'
Net income (loss)	-21,205,035		15,372,649
Adjustments to reconcile net income (loss) to net cash used in operating activities:	'		'
(Increase) decrease in commodity futures trading account - cash and cash equivalents	-10,827,518		782,252
Unrealized gain on open futures contracts	-6,013,022		-31,016,267
Increase in interest receivable	-787		-357
Increase in other assets	-14,274		-8,286
Increase (decrease) in management fees payable	28,138		28,693
Increase (decrease) in professional fees payable	-77,049		16,664
Decrease in brokerage commissions payable	0		-3,380
Increase (decrease) in other liabilities	3,995		-8,271
Net cash used in operating activities	-38,105,552		-14,836,303
Cash Flows from Financing Activities:	'		'
Addition of units	102,973,280		117,529,211
Redemption of units	-19,401,785		-17,511,744
Net cash provided by financing activities	83,571,495		100,017,467
Net Increase in Cash and Cash Equivalents	45,465,943		85,181,164
Cash and Cash Equivalents, beginning of period	430,800,077		310,491,998
Cash and Cash Equivalents, end of period	476,266,020		395,673,162
United States Copper Index Fund [Member]	'		'
Cash Flows from Operating Activities:	'		'
Net income (loss)	-281,264		198,814
Adjustments to reconcile net income (loss) to net cash used in operating activities:	'		'
(Increase) decrease in commodity futures trading account - cash and cash equivalents	214,344		242,685
Unrealized gain on open futures contracts	-18,500		-278,838
(Increase) decrease in receivable from Sponsor	29,192		-52,453
Increase in interest receivable	-7		0
Increase in other assets	-61		-74
Increase (decrease) in management fees payable	-204		-612
Increase (decrease) in professional fees payable	-30,421		54,516
Increase in other liabilities	5		30
Net cash used in operating activities	-86,916		164,068
Cash Flows from Financing Activities:	'		'
Addition of units	0		1,224,883
Redemption of units	0		-1,240,510
Net cash provided by financing activities	0		-15,627
Net Increase in Cash and Cash Equivalents	-86,916		148,441
Cash and Cash Equivalents, beginning of period	2,109,061		2,114,061
Cash and Cash Equivalents, end of period	2,022,145		2,262,502
United States Agriculture Index Fund [Member]	'		'
Cash Flows from Operating Activities:	'		'
Net income (loss)	-188,222	[1]	374,618	[1]
Adjustments to reconcile net income (loss) to net cash used in operating activities:	'		'
(Increase) decrease in commodity futures trading account - cash and cash equivalents	292,874		-638,131
Unrealized gain on open futures contracts	-83,227		-18,483
(Increase) decrease in receivable from Sponsor	-285		-46,719
Increase in interest receivable	-14		-21
Increase in other assets	-89		0
Increase (decrease) in management fees payable	-210		1,821
Increase (decrease) in professional fees payable	-200		48,566
Increase in other liabilities	6		79
Net cash used in operating activities	20,633		-278,270
Cash Flows from Financing Activities:	'		'
Addition of units	0		5,085,695
Redemption of units	0		-2,723,566
Net cash provided by financing activities	0		2,362,129
Net Increase in Cash and Cash Equivalents	20,633		2,083,859
Cash and Cash Equivalents, beginning of period	2,000,438		1,000
Cash and Cash Equivalents, end of period	2,021,071		2,084,859
United States Metals Index Fund [Member]	'		'
Cash Flows from Operating Activities:	'		'
Net income (loss)	-325,335		302,607
Adjustments to reconcile net income (loss) to net cash used in operating activities:	'		'
(Increase) decrease in commodity futures trading account - cash and cash equivalents	42,797		-353,011
Unrealized gain on open futures contracts	73,253		-175,713
(Increase) decrease in receivable from Sponsor	-17,862		-29,177
Increase in interest receivable	-4		-21
Increase in other assets	-93		0
Increase (decrease) in management fees payable	-165		1,549
Increase (decrease) in professional fees payable	18,507		30,141
Increase in other liabilities	25		81
Net cash used in operating activities	-208,877		-223,544
Cash Flows from Financing Activities:	'		'
Addition of units	1,089,776		3,727,317
Redemption of units	-1,136,000		-1,264,396
Net cash provided by financing activities	-46,224		2,462,921
Net Increase in Cash and Cash Equivalents	-255,101		2,239,377
Cash and Cash Equivalents, beginning of period	2,136,984		1,000
Cash and Cash Equivalents, end of period	$1,881,883		$2,240,377

[1]	The commencement of operations of the United States Agriculture Index Fund was April 13, 2012.

Organization_And_Business

Organization And Business	9 Months Ended
Organization And Business	Sep. 30, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Organization And Business	'
	NOTE 1 - ORGANIZATION AND BUSINESS

	The United States Commodity Index Funds Trust (the “Trust”) was organized as a Delaware statutory trust on December 21, 2009. The Trust is a series trust formed pursuant to the Delaware Statutory Trust Act and includes the United States Commodity Index Fund (“USCI”), a commodity pool formed on April 1, 2010 and first made available to the public on August 10, 2010, the United States Copper Index Fund (“CPER”), a commodity pool formed on November 26, 2010 and first made available to the public on November 15, 2011, the United States Agriculture Index Fund (“USAG”), a commodity pool formed on November 26, 2010 and first made available to the public on April 13, 2012 and the United States Metals Index Fund (“USMI”), a commodity pool formed on November 26, 2010 and first made available to the public on June 19, 2012. USCI, CPER, USAG and USMI each issues units (“units”) that may be purchased and sold on the NYSE Arca, Inc. (the “NYSE Arca”). USCI, CPER, USAG and USMI are collectively referred to herein as the “Trust Series.” The Trust and each Trust Series operate pursuant to the Third Amended and Restated Declaration of Trust and Trust Agreement dated as of March 22, 2013 (the “Trust Agreement”). United States Commodity Funds LLC (“USCF”) is the sponsor of the Trust and the Trust Series and is also responsible for the management of the Trust and the Trust Series. For purposes of the financial statement presentation, unless specified otherwise, all references will be to the Trust Series.

	USCF has the power and authority to establish and designate one or more series and to issue units thereof, from time to time as it deems necessary or desirable. USCF has exclusive power to fix and determine the relative rights and preferences as between the units of any series as to right of redemption, special and relative rights as to dividends and other distributions and on liquidation, conversion rights, and conditions under which the series shall have separate voting rights or no voting rights. The term for which the Trust is to exist commenced on the date of the filing of the Certificate of Trust, and the Trust and any Trust Series will exist in perpetuity, unless earlier terminated in accordance with the provisions of the Trust Agreement. Separate and distinct records must be maintained for each Trust Series and the assets associated with a Trust Series must be held in such separate and distinct records (directly or indirectly, including a nominee or otherwise) and accounted for in such separate and distinct records separately from the assets of any other Trust Series. Each Trust Series is separate from all other Trust Series created as series of the Trust in respect of the assets and liabilities allocated to that Trust Series and represents a separate investment portfolio of the Trust.

	The sole Trustee of the Trust is Wilmington Trust Company (the “Trustee”), a Delaware banking corporation. The Trustee is unaffiliated with USCF. The Trustee’s duties and liabilities with respect to the offering of units and the management of the Trust are limited to its express obligations under the Trust Agreement.

	USCF is a member of the National Futures Association (the “NFA”) and became a commodity pool operator (“CPO”) registered with the Commodity Futures Trading Commission (the “CFTC”) effective December 1, 2005. The Trust and each Trust Series have a fiscal year ending on December 31.

	USCF is also the general partner of the United States Oil Fund, LP (“USOF”), the United States Natural Gas Fund, LP (“USNG”), the United States 12 Month Oil Fund, LP (“US12OF”), the United States Gasoline Fund, LP (“UGA”) and the United States Diesel-Heating Oil Fund, LP (formerly, the United States Heating Oil Fund, LP) (“USDHO”), which listed their limited partnership units on the American Stock Exchange (the “AMEX”) under the ticker symbols “USO” on April 10, 2006, “UNG” on April 18, 2007, “USL” on December 6, 2007, “UGA” on February 26, 2008 and “UHN” on April 9, 2008, respectively. As a result of the acquisition of the AMEX by NYSE Euronext, each of USOF’s, USNG’s, US12OF’s, UGA’s and USDHO’s units commenced trading on the NYSE Arca on November 25, 2008. USCF is also the general partner of the United States Short Oil Fund, LP (“USSO”), the United States 12 Month Natural Gas Fund, LP (“US12NG”) and the United States Brent Oil Fund, LP (“USBO”), which listed their limited partnership units on the NYSE Arca under the ticker symbols “DNO” on September 24, 2009, “UNL” on November 18, 2009 and “BNO” on June 2, 2010, respectively. All funds listed previously are referred to collectively herein as the “Related Public Funds.” USCF has also filed registration statements to register units of the United States Sugar Fund (“USSF”), the United States Natural Gas Double Inverse Fund (“UNGD”), the United States Gasoil Fund (“USGO”) and the United States Asian Commodities Basket Fund (“UAC”), each a series of the United States Commodity Funds Trust I, and the US Golden Currency Fund (“HARD”), a series of the United States Currency Funds Trust. USSF, UNGD, USGO and HARD are currently not available to the public, as such funds are still in the process of review by various regulatory agencies which have regulatory authority over USCF and such funds. UAC has been declared effective by the regulatory agencies which have regulatory authority over USCF and UAC, but at the time of the filing of this quarterly report on Form 10-Q, UAC has not been made available to the public.

	Effective as of May 1, 2012, each of USCI, CPER and USAG issue units to certain authorized purchasers (“Authorized Purchasers”) by offering baskets consisting of 50,000 units (“Creation Baskets”) through ALPS Distributors, Inc., as the marketing agent (the “Marketing Agent”). Prior to May 1, 2012, each of USCI, CPER and USAG issued units to Authorized Purchasers by offering baskets consisting of 100,000 units through the Marketing Agent. USMI was not available to the public until June 19, 2012, and from its inception of offering, issues units to certain Authorized Purchasers by offering baskets consisting of 50,000 units through the Marketing Agent. The purchase price for a Creation Basket is based upon the net asset value (“NAV”) of a unit calculated shortly after the close of the core trading session on the NYSE Arca on the day the order to create the basket is properly received.

	From July 1, 2011 through September 30, 2013 (and continuing at least through May 1, 2014), Authorized Purchasers pay USCI $350 for each order placed to create one or more Creation Baskets or to redeem one or more baskets (“Redemption Baskets”), consisting of 50,000 units; prior to July 1, 2011, this fee was $1,000. From May 1, 2012 through September 30, 2013 (and continuing at least through May 1, 2014), Authorized Purchasers pay each of CPER, USAG and USMI $350 for each order placed to create one or more Creation Baskets or to redeem one or more Redemption Baskets; prior to May 1, 2012, this fee was $1,000. Units may be purchased or sold on a nationally recognized securities exchange in smaller increments than a Creation Basket or Redemption Basket. Units purchased or sold on a nationally recognized securities exchange are not purchased or sold at the per unit NAV of each Trust Series but rather at market prices quoted on such exchange.

	The accompanying unaudited condensed financial statements have been prepared in accordance with Rule 10-01 of Regulation S-X promulgated by the U.S. Securities and Exchange Commission (the “SEC”) and, therefore, do not include all information and footnote disclosure required under generally accepted accounting principles (“GAAP”) in the United States of America. The financial information included herein is unaudited; however, such financial information reflects all adjustments, consisting only of normal recurring adjustments, which are, in the opinion of USCF, necessary for the fair presentation of the condensed financial statements for the interim period.

Summary_Of_Significant_Account

Summary Of Significant Accounting Policies	9 Months Ended
Summary Of Significant Accounting Policies	Sep. 30, 2013
Accounting Policies [Abstract]	'
Summary Of Significant Accounting Policies	'
	NOTE 2 - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

	Revenue Recognition

	Commodity futures contracts, forward contracts, physical commodities, and related options are recorded on the trade date. All such transactions are recorded on the identified cost basis and marked to market daily. Unrealized gains or losses on open contracts are reflected in the condensed statements of financial condition and represent the difference between the original contract amount and the market value (as determined by exchange settlement prices for futures contracts and related options and cash dealer prices at a predetermined time for forward contracts, physical commodities, and their related options) as of the last business day of the year or as of the last date of the condensed financial statements. Changes in the unrealized gains or losses between periods are reflected in the condensed statements of operations. Each Trust Series earns interest on its assets denominated in U.S. dollars on deposit with the futures commission merchant at the 90-day Treasury bill rate. In addition, each Trust Series earns income on funds held at the custodian and/or futures commission merchant at prevailing market rates earned on such investments.

	Brokerage Commissions

	Brokerage commissions on all open commodity futures contracts are accrued on a full-turn basis.

	Income Taxes

	The Trust Series are not subject to federal income taxes; each investor reports his/her allocable share of income, gain, loss deductions or credits on his/her own income tax return.

	In accordance with accounting principles generally accepted in the United States of America (“GAAP”), each Trust Series is required to determine whether a tax position is more likely than not to be sustained upon examination by the applicable taxing authority, including resolution of any tax related appeals or litigation processes, based on the technical merits of the position. Each Trust Series files an income tax return in the U.S. federal jurisdiction, and may file income tax returns in various U.S. states. None of the Trust Series is subject to income tax return examinations by major taxing authorities for years before 2010 (year of the Trust Series’ inception, but not necessarily the commencement of operations for each Trust Series). The tax benefit recognized is measured as the largest amount of benefit that has a greater than fifty percent likelihood of being realized upon ultimate settlement. De-recognition of a tax benefit previously recognized results in each Trust Series recording a tax liability that reduces net assets. However, each Trust Series’ conclusions regarding this policy may be subject to review and adjustment at a later date based on factors including, but not limited to, on-going analysis of and changes to tax laws, regulations and interpretations thereof. Each Trust Series recognizes interest accrued related to unrecognized tax benefits and penalties related to unrecognized tax benefits in income tax fees payable, if assessed. No interest expense or penalties have been recognized as of and for the period ended September 30, 2013 for any Trust Series.

	Trust Capital and Allocation of Income and Losses

	Profit or loss shall be allocated among the unitholders of each Trust Series in proportion to the number of units each investor holds as of the close of each month. USCF may revise, alter or otherwise modify this method of allocation as described in the Trust Agreement.

	Adoption of New Monthly Allocation Convention

	Effective January 1, 2012, USCI adopted a new convention for allocating items of income, gain, loss, deduction and credits. In situations where a partner’s interest in a partnership is sold or otherwise transferred during a taxable year, the Code generally requires that partnership tax items for the year be allocated among the partners using either an interim closing of the books or a daily proration method. USCI uses an interim closing of the books method under which income, gains and losses (both realized and unrealized), deductions and credits are determined on a monthly basis. Prior to January 1, 2012, USCI allocated these tax items among the holders of the units (including those who dispose of units during a taxable year) in proportion to the number of units owned by them on the last trading day of each month. For this purpose, if an investor holds a unit as of the close of business of the last trading day of a particular month, such investor is treated as if it owned the unit throughout the month and thus is allocated all of the items of income, gain, deduction, loss or credit attributable to that unit for such month (the “same-month convention”).

	Effective January 1, 2012 for USCI, November 15, 2011 for CPER, April 13, 2012 for USAG and June 19, 2012 for USMI, an allocation convention is applied pursuant to which each Trust Series’ tax items for each month will be allocated among the holders of units in proportion to the number of units owned by them as of the close of business of the last trading day of the previous month. If an investor who holds a unit as of the close of business on the last trading day of the previous month disposes of a unit during the current month, such investor will be treated for purposes of making allocations as if it owned the unit throughout the current month (the “next-month convention”). For example, an investor who buys a unit on April 10 of a year and sells it on May 20 of the same year will be allocated all of the tax items attributable to May (because he or she is deemed to hold it through the last day of May) but will not be allocated any of the tax items attributable to April. The tax items attributable to that unit for April will be allocated to the person who is the actual or deemed holder of the unit as of the close of business on the last trading day of March.

	For investors in USCI, as a result of the transition from the same-month convention to the next-month convention, an investor who bought a unit in December 2011 and sold the unit on or after January 1, 2012 will be allocated the tax items attributable to that unit for December 2011 as well as the tax items attributable to that unit for 2012.

	Creations and Redemptions

	Effective as of May 1, 2012, Authorized Purchasers may purchase Creation Baskets or redeem Redemption Baskets for USCI, CPER and USAG only in blocks of 50,000 units at a price equal to the NAV of the units calculated shortly after the close of the core trading session on the NYSE Arca on the day the order is placed. Prior to May 1, 2012, Authorized Purchasers could only purchase Creation Baskets or redeem Redemption Baskets for USCI, CPER and USAG in blocks of 100,000 units. USMI was not available to the public until June 19, 2012, and from its inception of offering, Authorized Purchasers could only purchase Creation Baskets in blocks of 50,000 units.

	Each Trust Series receives or pays the proceeds from units sold or redeemed within three business days after the trade date of the purchase or redemption. The amounts due from Authorized Purchasers are reflected in each Trust Series’ condensed statements of financial condition as receivable for units sold, and amounts payable to Authorized Purchasers upon redemption are reflected as payable for units redeemed.

	Calculation of Net Asset Value Per Unit

	Each Trust Series’ per unit NAV is calculated on each NYSE Arca trading day by taking the current market value of its total assets, subtracting any liabilities and dividing the amount by the total number of units outstanding. Each Trust Series uses the closing prices on the relevant Futures Exchanges (as defined in Note 3 below) of the Applicable Benchmark Component Futures Contracts (as defined in Note 3 below) that at any given time make up the Applicable Index (as defined in Note 3 below) (determined at the earlier of the close of such exchange or 2:30 p.m. New York time) for the contracts traded on the Futures Exchanges, but calculates or determines the value of all other investments of each Trust Series using market quotations, if available, or other information customarily used to determine the fair value of such investments.

	Net Income (Loss) Per Unit

	Net income (loss) per unit is the difference between the per unit NAV at the beginning of each period and the per unit NAV at the end of each period. The weighted average number of units outstanding was computed for purposes of disclosing net income (loss) per weighted average unit. The weighted average units are equal to the number of units outstanding at the end of the period, adjusted proportionately for units added and redeemed based on the amount of time the units were outstanding during such period. As of September 30, 2013, USCF held 5 units of USMI. As of September 30, 2013, USCF held 5 units of USCI, held 40 units of CPER and held 5 units of USAG.

	Offering Costs

	Offering costs incurred in connection with the registration of units prior to the commencement of the offering are borne by USCF. Offering costs incurred in connection with the registration of additional units after the commencement of the offering are borne by each Trust Series. These costs include registration fees paid to regulatory agencies and all legal, accounting, printing and other expenses associated with such offerings. Costs borne by the Trust Series after the commencement of an offering are accounted for as a deferred charge and thereafter amortized to expense over twelve months on a straight-line basis or a shorter period if warranted.

	Cash Equivalents

	Cash equivalents include money market funds and overnight deposits or time deposits with original maturity dates of six months or less.

	Use of Estimates

	The preparation of condensed financial statements in conformity with GAAP requires USCF to make estimates and assumptions that affect the reported amount of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed financial statements, and the reported amounts of the revenue and expenses during the reporting period. Actual results may differ from those estimates and assumptions.

Trust_Series

Trust Series	9 Months Ended
Trust Series	Sep. 30, 2013
Trust Series [Abstract]	'
Trust Series	'
	NOTE 3 - TRUST SERIES

	In connection with the execution of the First Trust Agreement on April 1, 2010, USCI was designated as the first series of the Trust. USCF contributed $1,000 to the Trust upon its formation on December 21, 2009, representing an initial contribution of capital to the Trust. Following the designation of USCI as the first series of the Trust, the initial capital contribution of $1,000 was transferred from the Trust to USCI and deemed an initial contribution to USCI. In connection with the commencement of USCI’s initial offering of units, USCF received 20 Sponsor Units of USCI in exchange for the previously received capital contribution, representing a beneficial ownership interest in USCI.

	On July 30, 2010, USCI received a notice of effectiveness from the SEC for its registration of 50,000,000 units on Form S-1 with the SEC. On August 10, 2010, USCI listed its units on the NYSE Arca under the ticker symbol “USCI”. USCI established its initial per unit NAV by setting the price at $50.00 and issued 100,000 units in exchange for $5,000,000 on August 10, 2010. USCI also commenced investment operations on August 10, 2010 by purchasing Futures Contracts traded on the Futures Exchanges. In order to satisfy NYSE Arca listing standards that at least 100,000 units be outstanding at the beginning of the trading day on the NYSE Arca, USCF purchased the initial Creation Basket from the initial Authorized Purchaser at the initial offering price. The $1,000 fee that would otherwise be charged to the Authorized Purchaser in connection with an order to create or redeem was waived in connection with the initial Creation Basket. USCF held such initial Creation Basket until September 3, 2010, at which time the initial Authorized Purchaser repurchased the units comprising such basket in accordance with the specified conditions noted above. On September 14, 2011, USCF redeemed the 20 Sponsor Units of USCI and, on September 19, 2011, USCF purchased five units of USCI in the open market.

	In connection with the Second Amended and Restated Trust Agreement dated November 10, 2010, USMI, USAG and CPER were designated as three additional series of the Trust. Following the designation of the additional series, an initial capital contribution of $3,000 was transferred from USCF to the Trust. On November 10, 2010, the Trust transferred $1,000 to each of USMI, USAG and CPER, which was deemed a capital contribution to each series. On November 14, 2011, USCF received 40 Sponsor Units of CPER in exchange for the previously received capital contribution, representing a beneficial interest in CPER. On December 7, 2011, USCF redeemed the 40 Sponsor Units of CPER and purchased 40 units of CPER in the open market. On April 13, 2012, USCF received 40 Sponsor Units of USAG in exchange for the previously received capital contribution, representing a beneficial interest in USAG. On June 28, 2012, USCF redeemed the 40 Sponsor Units of USAG and on October 3, 2012, purchased 5 units of USAG on the open market. On June 19, 2012, USCF received 40 Sponsor Units of USMI in exchange for the previously received capital contribution, representing a beneficial interest in USMI. On August 27, 2012, USCF redeemed the 40 Sponsor Units of USMI and, on September 4, 2013, purchased 5 units of USMI on the open market.

	CPER, USAG and USMI received notice of effectiveness from the SEC for its registration of 30,000,000 CPER units, 20,000,000 USAG units and 20,000,000 USMI units on September 6, 2011. The order to permit listing CPER, USAG and USMI on the NYSE Arca was received on October 20, 2011. On November 15, 2011, CPER listed its units on the NYSE Arca under the ticker symbol “CPER.” CPER established its initial per unit NAV by setting the price at $25.00 and issued 100,000 units to the initial authorized purchaser in exchange for $2,500,000 in cash on November 15, 2011. The $1,000 fee that would otherwise have been charged to the Authorized Purchaser in connection with an order to create or redeem was waived in connection with the initial Creation Basket.

	On April 13, 2012, USAG listed its units on the NYSE Arca under the ticker symbol “USAG.” USAG established its initial per unit NAV by setting the price at $25.00. On April 14, 2012, USCF purchased two initial Creation Baskets of USAG. In accordance with applicable requirements of Regulation M under the Securities Exchange Act of 1934, no Creation Baskets were offered to Authorized Purchasers nor were the units listed on the NYSE Arca until five business days had elapsed from the date of USCF’s purchase of the initial Creation Basket on April 4, 2012. The $1,000 fee that would have otherwise been charged in connection with an order to create or redeem was waived in connection with the initial Creation Basket.

	On June 19, 2012, USMI listed its units on the NYSE Arca under the ticker symbol “USMI.” USMI established its initial per unit NAV by setting the price at $25.00. On June 11, 2012, USCF purchased two initial Creation Baskets of USMI. In accordance with applicable requirements of Regulation M under the Securities Exchange Act of 1934, no Creation Baskets were offered to Authorized Purchasers nor were the units listed on the NYSE Arca until five business days had elapsed from the date of USCF’s purchase of the initial Creation Basket on June 11, 2012. The $350 fee that would have otherwise been charged in connection with an order to create or redeem was waived in connection with the initial Creation Basket. On September 4, 2013, USCF redeemed the second of two initial Creation Baskets.

	USCI’s Investment Objective

	USCI invests in futures contracts for commodities that are currently traded on the New York Mercantile Exchange (the “NYMEX”), ICE Futures (“ICE Futures”), Chicago Board of Trade (“CBOT”), Chicago Mercantile Exchange (“CME”), London Metal Exchange (“LME”), Commodity Exchange, Inc. (“COMEX”) or on other foreign exchanges (the NYMEX, ICE Futures, CBOT, CME, LME, COMEX and other foreign exchanges, collectively, the “Futures Exchanges”) (such futures contracts, collectively, “Futures Contracts”) and, to a lesser extent, in order to comply with regulatory requirements or in view of market conditions, other commodity-based contracts and instruments such as cash-settled options on Futures Contracts, forward contracts relating to commodities, cleared swap contracts and other non exchange traded (“over-the-counter”) transactions that are based on the price of commodities and Futures Contracts (collectively, “Other Commodity-Related Investments”). Market conditions that USCF currently anticipates could cause USCI to invest in Other Commodity Related Investments would be those allowing USCI to obtain greater liquidity or to execute transactions with more favorable pricing. Futures Contracts and Other Commodity-Related Investments collectively are referred to as “Commodity Interests.”

	The investment objective of USCI is for the daily changes in percentage terms of its units’ per unit net asset value (“NAV”) to reflect the daily changes in percentage terms of the SummerHaven Dynamic Commodity Index Total Return^SM (the “Commodity Index”), less USCI’s expenses. USCF does not intend to operate USCI in a fashion such that its per unit NAV will equal, in dollar terms, the spot prices of the commodities underlying the Benchmark Component Futures Contracts (as defined below) that comprise the Commodity Index or the prices of any particular group of Futures Contracts. USCI will not seek to achieve its stated investment objective over a period of time greater than one day. USCI believes that it is not practical to manage the portfolio to achieve such an investment goal when investing in Futures Contracts and Other Commodity-Related Investments. The Commodity Index is designed to reflect the performance of a diversified group of commodities. The Commodity Index is comprised of 14 Futures Contracts that are selected on a monthly basis from a list of 27 possible Futures Contracts. The Futures Contracts that at any given time make up the Commodity Index are referred to herein as “Benchmark Component Futures Contracts.” The Commodity Index is owned and maintained by SummerHaven Index Management, LLC (“SummerHaven Indexing”) and calculated and published by Bloomberg, L.P. USCI invests first in the current Benchmark Component Futures Contracts and other Futures Contracts intended to replicate the return on the current Benchmark Component Futures Contracts and, thereafter may hold Futures Contracts in a particular commodity other than one specified as the Benchmark Component Futures Contract, or may hold Other Commodity-Related Investments that are intended to replicate the return on the Benchmark Futures Contracts, but may fail to closely track the Commodity Index’s total return movements. If USCI increases in size, and due to its obligations to comply with regulatory limits or due to other market pricing or liquidity factors, USCI may invest in Futures Contract months other than the designated month specified as the Benchmark Component Futures Contract, or in Other Commodity-Related Investments, which may have the effect of increasing transaction related expenses and may result in increased tracking error.

	USCI’s units began trading on August 10, 2010. As of September 30, 2013, USCI held 2,660 Futures Contracts on the NYMEX, 2,816 Futures Contracts on the ICE Futures, 936 Futures Contracts on the CBOT, 2,312 Futures Contracts on the CME and 5,643 Futures Contracts on the LME and 477 Futures Contracts on the COMEX, totaling 14,844 futures contracts.

	CPER’s Investment Objective

	The investment objective of CPER is for the daily changes in percentage terms of its units’ per unit NAV to reflect the daily changes in percentage terms of the SummerHaven Copper Index Total Return^SM (the “Copper Index”), less CPER’s expenses. USCF does not intend to operate CPER in a fashion such that its per unit NAV will equal, in dollar terms, the spot prices of the commodities underlying the Benchmark Component Copper Futures Contracts (as defined below) that comprise the Copper Index or the prices of any particular group of Futures Contracts. CPER will not seek to achieve a stated investment objective over a period of time greater than one day. USCF believes that it is not practical to manage the portfolio to achieve such an investment goal when investing in Futures Contracts and Other Copper-Related Investments (as defined below). The Copper Index is designed to reflect the performance of the investment returns from a portfolio of copper futures contracts. The Copper Index is owned and maintained by SummerHaven Indexing and calculated and published by the NYSE Arca. The Copper Index is comprised of either two or three Eligible Copper Futures Contracts that are selected on a monthly basis based on quantitative formulas relating to the prices of the Eligible Copper Futures Contracts developed by SummerHaven Indexing. The Eligible Copper Futures Contracts that at any given time make up the Copper Index are referred to herein as “Benchmark Component Copper Futures Contracts.”

	CPER seeks to achieve its investment objective by investing to the fullest extent possible in the Benchmark Component Copper Futures Contracts. Then, if constrained by regulatory requirements or in view of market conditions, CPER will invest next in other Eligible Copper Futures Contracts, and finally to a lesser extent, in other exchange traded futures contracts that are economically identical or substantially similar to the Benchmark Component Copper Futures Contracts if one or more other Eligible Copper Futures Contracts is not available. When CPER has invested to the fullest extent possible in exchange-traded futures contracts, CPER may then invest in other contracts and instruments based on the Benchmark Component Copper Futures Contracts, other Eligible Copper Futures Contracts or copper, such as cash-settled options, forward contracts, cleared swap contracts and swap contracts other than cleared swap contracts. Other exchange-traded futures contracts that are economically identical or substantially similar to the Benchmark Component Copper Futures Contracts and other contracts and instruments based on the Benchmark Component Copper Futures Contracts, are collectively referred to as “Other Copper-Related Investments,” and together with Benchmark Component Copper Futures Contracts and other Eligible Copper Futures Contracts, “Copper Interests.” CPER’s units began trading on November 15, 2011. As of September 30, 2013, CPER held 27 Futures Contracts on the COMEX.

	USAG’s Investment Objective

	The investment objective of USAG is for the daily changes in percentage terms of its units’ per unit NAV to reflect the daily changes in percentage terms of the SummerHaven Dynamic Agriculture Index Total Return^SM (the “Agriculture Index”), less USAG’s expenses. USCF does not intend to operate USAG in a fashion such that its per unit NAV will equal, in dollar terms, the spot prices of the commodities underlying the Benchmark Component Agriculture Futures Contracts (as defined below) that comprise the Agriculture Index or the prices of any particular group of Futures Contracts. USAG will not seek to achieve its stated investment objective over a period of time greater than one day. USCF believes that it is not practical to manage the portfolio to achieve such an investment goal when investing in Futures Contracts and Other Agriculture-Related Investments (as defined below). The Agriculture Index is designed to reflect the performance of a diversified group of agricultural commodities. The Agriculture Index is owned and maintained by SummerHaven Indexing and calculated and published by the NYSE Arca. Futures contracts for the agricultural commodities comprising the Agriculture Index are traded on ICE Future US, ICE Futures Canada, the CBOT, the Kansas City Board of Trade (“KCBT”) and the CME and are collectively referred to herein as “Eligible Agriculture Futures Contracts.” The Agriculture Index is comprised of 14 Eligible Agriculture Futures Contracts that are selected on a monthly basis based on quantitative formulas developed by SummerHaven Indexing. The Eligible Agriculture Futures Contracts that at any given time make up the Agriculture Index are referred to herein as “Benchmark Component Agriculture Futures Contracts.” The relative weighting of the Benchmark Component Agriculture Futures Contracts will change on a monthly basis, based on quantitative formulas relating to the prices of the Benchmark Component Agriculture Futures Contracts developed by SummerHaven Indexing.

	USAG seeks to achieve its investment objective by investing to the fullest extent possible in the Benchmark Component Agriculture Futures Contracts. Then, if constrained by regulatory requirements or in view of market conditions, USAG will invest next in other Eligible Agriculture Futures Contracts based on the same agricultural commodity as the futures contracts subject to such regulatory constraints or market conditions, and finally, to a lesser extent, in other exchange traded futures contracts that are economically identical or substantially similar to the Benchmark Component Agriculture Futures Contracts if one or more other Eligible Agriculture Futures Contracts is not available. When USAG has invested to the fullest extent possible in exchange-traded futures contracts, USAG may then invest in other contracts and instruments based on the Benchmark Component Agriculture Futures Contracts, other Eligible Agriculture Futures Contracts or the agricultural commodities included in the Agriculture Index, such as cash-settled options, forward contracts, cleared swap contracts and swap contracts other than cleared swap contracts. Other exchange-traded futures contracts that are economically identical or substantially similar to the Benchmark Component Agriculture Futures Contracts and other contracts and instruments based on the Benchmark Component Agriculture Futures Contracts, as well as metals included in the Agriculture Index, are collectively referred to as “Other Agriculture-Related Investments,” and together with Benchmark Component Agriculture Futures Contracts and other Eligible Agriculture Futures Contracts, “Agriculture Interests.” USAG’s units began trading on April 13, 2012. As of September 30, 2013, USAG held 29 Futures Contracts on the ICE Futures, 14 Futures Contracts on the CME, 1 Futures Contract on the KCBT and 25 Futures Contracts on the CBOT, totaling 69 futures contracts.

	USMI’s Investment Objective

	The investment objective of USMI is for the daily changes in percentage terms of its units’ per unit NAV to reflect the daily changes in percentage terms of the SummerHaven Metals Index Total Return^SM (the “Metals Index”), less USMI’s expenses. USCF does not intend to operate USMI in a fashion such that its per unit NAV will equal, in dollar terms, the spot prices of the commodities underlying the Benchmark Component Metals Futures Contracts (as defined below) that comprise the Metals Index or the prices of any particular group of Futures Contracts. USMI will not seek to achieve its stated investment objective over a period of time greater than one day. USCF believes that it is not practical to manage the portfolio to achieve such an investment goal when investing in Futures Contracts and Other Metals-Related Investments (as defined below). The Metals Index is owned and maintained by SummerHaven Indexing and calculated and published by the NYSE Arca. Futures contracts for the metals in the Metals Index that are traded on the NYMEX, the LME and COMEX are collectively referred to herein as “Eligible Metals Futures Contracts.” The Metals Index is comprised of 10 Eligible Metals Futures Contracts that are selected on a monthly basis based on quantitative formulas developed by SummerHaven Indexing. The Eligible Metals Futures Contracts that at any given time make up the Metals Index are referred to herein as “Benchmark Component Metals Futures Contracts.” The relative weighting of the Benchmark Component Metals Futures Contracts will change on a monthly basis, based on quantitative formulas relating to the prices of the Benchmark Component Metals Futures Contracts developed by SummerHaven Indexing.

	USMI seeks to achieve its investment objective by investing to the fullest extent possible in the Benchmark Component Metals Futures Contracts. Then, if constrained by regulatory requirements or in view of market conditions, USMI will invest next in other Eligible Metals Futures Contracts, and finally to a lesser extent, in other exchange traded futures contracts that are economically identical or substantially similar to the Benchmark Component Metals Futures Contracts if one or more other Eligible Metals Futures Contracts is not available. When USMI has invested to the fullest extent possible in exchange-traded futures contracts, USMI may then invest in other contracts and instruments based on the Benchmark Component Metals Futures Contracts, other Eligible Metals Futures Contracts or the metals included in the Metals Index, such as cash-settled options, forward contracts, cleared swap contracts and swap contracts other than cleared swap contracts. Other exchange-traded futures contracts that are economically identical or substantially similar to the Benchmark Component Metals Futures Contracts and other contracts and instruments based on the Benchmark Component Metals Futures Contracts are collectively referred to as “Other Metals-Related Investments,” and together with Benchmark Component Metals Futures Contracts and other Eligible Metals Futures Contracts, “Metals Interests.” USMI’s units began trading on June 19, 2012. As of September 30, 2013, USMI held 2 Futures Contracts on the NYMEX, 44 Futures Contracts on the LME and 13 Futures Contracts on the COMEX, totaling 59 futures contracts.

	Other Defined Terms – Trust Series

	The Commodity Index, the Copper Index, the Agriculture Index and the Metals Index are referred to throughout these Notes to Financial Statements collectively as the “Applicable Index” or “Indices.”

	Benchmark Component Futures Contracts, Benchmark Component Copper Futures Contracts, Benchmark Component Agriculture Futures Contracts and Benchmark Component Metals Futures Contracts are referred to throughout these Notes to Financial Statements collectively as “Applicable Benchmark Component Futures Contracts.”

	Other Commodity-Related Investments, Other Copper-Related Investments, Other Agriculture-Related Interests and Other Metals-Related Investments are referred to throughout these Notes to Financial Statements collectively as “Other Related Investments.”

	Trading Advisor and Trustee

	The Trust Series’ trading advisor is SummerHaven Investment Management, LLC (“SummerHaven”), a Delaware limited liability company that is registered as a commodity trading advisor and CPO with the CFTC and is a member of the NFA. SummerHaven provides advisory services to USCF with respect to the Applicable Index of each Trust Series and the investment decisions of each Trust Series.

	The Trustee accepts service of legal process on the Trust in the State of Delaware and makes certain filings under the Delaware Statutory Trust Act. The Trustee does not owe any other duties to the Trust, USCF or the unitholders.

Fees_Paid_By_Each_Trust_Series

Fees Paid By Each Trust Series And Related Party Transactions	9 Months Ended
	Sep. 30, 2013
Fees Paid By Usci and Cper and Related Party Transactions [Abstract]	'
Fees Paid by Usci and Cper and Related Party Transactions	'
	NOTE 4 - FEES PAID BY EACH TRUST SERIES AND RELATED PARTY TRANSACTIONS

	USCF Management Fee

	Under the Trust Agreement, USCF is responsible for investing the assets of each Trust Series in accordance with the objectives and policies of each such Trust Series. In addition, USCF has arranged for one or more third parties to provide trading advisory, administrative, custody, accounting, transfer agency and other necessary services to each Trust Series. For these services, each of USCI, CPER, USAG and USMI is contractually obligated to pay USCF a fee, which is paid monthly, equal to 0.95% per annum of average daily total net assets. Effective as of May 29, 2012 (and continuing at least through May 1, 2014), USCF voluntarily waived the management fee paid by each of CPER and USAG from 0.95% per annum of average daily total net assets to 0.65% and 0.80% per annum of average daily total net assets, respectively. Effective as of May 30, 2012 (and continuing at least through May 1, 2014), USCF voluntarily waived the management fee paid by USMI from 0.95% per annum of average daily total net assets to 0.70% per annum of average daily total net assets. The reduced fee for USMI became operational as of June 19, 2012, when USMI first became listed on the NYSE Arca and will continue at least through May 1, 2014.

	Trustee Fee

	The Trustee is the Delaware trustee of the Trust. In connection with the Trustee’s services, USCF is responsible for paying the Trustee’s annual fee in the amount of $3,000.

	Ongoing Registration Fees and Other Offering Expenses

	Each Trust Series pays the costs and expenses associated with the ongoing registration of its units subsequent to the initial offering. These costs include registration or other fees paid to regulatory agencies in connection with the offer and sale of units, and all legal, accounting, printing and other expenses associated with such offer and sale. During the nine months ended September 30, 2013 and 2012, none of the Trust Series incurred any registration fees or other offering expenses.

	Directors’ Fees and Expenses

	Each Trust Series is responsible for paying its portion of the directors’ and officers’ liability insurance for such Trust Series and the Related Public Funds. In addition, as of July 8, 2011, each Trust Series is responsible for paying the fees and expenses of the independent directors who also serve as audit committee members of the Trust Series and the Related Public Funds organized as limited partnerships. Each Trust Series shares the fees and expenses on a pro rata basis with each other Trust Series and each Related Public Fund, as described above, based on the relative assets of each fund computed on a daily basis. These fees and expenses for the year ending December 31, 2013 are estimated to be a total of $560,625 for the Trust Series and the Related Public Funds.

	Investor Tax Reporting Cost

	The fees and expenses associated with each Trust Series’ audit expenses and tax accounting and reporting requirements are paid by such Trust Series. These costs are estimated to be $400,000 for the year ending December 31, 2013 for USCI, $60,000 for the year ending December 31, 2013 for CPER, $60,000 for the year ending December 31, 2013 for USAG and $60,000 for the year ending December 31, 2013 for USMI.

	Other Expenses and Fees and Expense Waivers

	In addition to the fees described above, each Trust Series pays all brokerage fees and other expenses in connection with the operation of such Trust Series, excluding costs and expenses paid by USCF as outlined in Note 5 below. In addition, USCF has voluntarily agreed to pay certain expenses normally borne by each of CPER, USAG and USMI to the extent that such expenses exceed 0.15% (15 basis points) of each of CPER’s, USAG’s and USMI’s NAV, on an annualized basis, through at least May 1, 2014. USCF has no obligation to continue such payments into subsequent periods. For the nine months ended September 30, 2013, USCF waived $67,171 in expenses for CPER, $77,135 for USAG and $77,178 for USMI. This voluntary expense waiver is in addition to those amounts USCF is contractually obligated to pay as described in Note 5.

Contracts_and_Agreements

Contracts and Agreements	9 Months Ended
Contracts and Agreements	Sep. 30, 2013
Contractors [Abstract]	'
Contracts and Agreements	'
	NOTE 5 - CONTRACTS AND AGREEMENTS

	USCF and the Trust, each on its own behalf and on behalf of each Trust Series, are party to a marketing agent agreement, dated as of July 22, 2010, as amended from time to time, with the Marketing Agent, whereby the Marketing Agent provides certain marketing services for each Trust Series as outlined in the agreement. The fee of the Marketing Agent, which is borne by USCF, is equal to 0.06% on each Trust Series’ assets up to $3 billion and 0.04% on each Trust Series’ assets in excess of $3 billion. In no event may the aggregate compensation paid to the Marketing Agent and any affiliate of USCF for distribution related services exceed 10% of the gross proceeds of each Trust Series’ offering.

	The above fee does not include the following expenses, which are also borne by USCF: the cost of placing advertisements in various periodicals; website construction and development; or the printing and production of various marketing materials.

	USCF and the Trust, on its own behalf and on behalf of each Trust Series, are also party to a custodian agreement, dated July 22, 2010, as amended from time to time, with Brown Brothers Harriman & Co. (“BBH&Co.”), whereby BBH&Co. holds investments on behalf of each Trust Series. USCF pays the fees of the custodian, which are determined by the parties from time to time. In addition, USCF and the Trust, on its own behalf and on behalf of each Trust Series, are party to an administrative agency agreement, dated July 22, 2010, as amended from time to time, with BBH&Co., whereby BBH&Co. acts as the administrative agent, transfer agent and registrar for each Trust Series. USCF also pays the fees of BBH&Co. for its services under such agreement and such fees are determined by the parties from time to time.

	Currently, USCF pays BBH&Co. for its services, in the foregoing capacities, a minimum amount of $75,000 annually for its custody, fund accounting and fund administration services rendered to each Trust Series and each of the Related Public Funds, as well as a $20,000 annual fee for its transfer agency services. In addition, USCF pays BBH&Co. an asset-based charge of: (a) 0.06% for the first $500 million of USCI’s, CPER’s, USAG’s, USMI’s, USOF’s, USNG’s, US12OF’s, UGA’s, USDHO’s, USSO’s, US12NG’s and USBO’s combined net assets, (b) 0.0465% for USCI’s, CPER’s, USAG’s, USMI’s, USOF’s, USNG’s, US12OF’s, UGA’s, USDHO’s, USSO’s, US12NG’s and USBO’s combined net assets greater than $500 million but less than $1 billion, and (c) 0.035% once USCI’s, CPER’s, USAG’s, USMI’s, USOF’s, USNG’s, US12OF’s, UGA’s, USDHO’s, USSO’s, US12NG’s and USBO’s combined net assets exceed $1 billion. The annual minimum amount will not apply if the asset-based charge for all accounts in the aggregate exceeds $75,000. USCF also pays transaction fees ranging from $7 to $15 per transaction.

	Each Trust Series has entered into a brokerage agreement, dated March 1, 2010 for USCI and November 18, 2011 for each of CPER, USAG and USMI, as amended from time to time, with Newedge USA, LLC (“Newedge”). The agreement requires Newedge to provide services to each Trust Series in connection with the purchase and sale of Futures Contracts and Other Related Investments that may be purchased and sold by or through Newedge for each Trust Series’ account. In accordance with the agreement, Newedge charges each Trust Series commissions of approximately $7 to $15 per round-turn trade, including applicable exchange and NFA fees for Futures Contracts and options on Futures Contracts. Such fees include those incurred when purchasing Futures Contracts and options on Futures Contracts when each Trust Series issues units as a result of a Creation Basket, as well as fees incurred when selling Futures Contacts and options on Futures Contracts when each Trust Series redeems units as a result of a Redemption Basket. Such fees are also incurred when Futures Contracts and options on Futures Contracts are purchased or redeemed for the purpose of rebalancing the portfolio. Each Trust Series also incurs commissions to brokers for the purchase and sale of Futures Contracts, Other Commodity-Related Investments or short-term obligations of the United States of two years or less (“Treasuries”). During the nine months ended September 30, 2013, total commissions accrued to brokers amounted to $284,139 for USCI. Of this amount, approximately $275,996 was a result of rebalancing costs and approximately $8,143 was the result of trades necessitated by creation and redemption activity for USCI. By comparison, during the nine months ended September 30, 2012, total commissions accrued to brokers amounted to $224,208 for USCI. Of this amount, approximately $30,573 was a result of rebalancing costs and approximately $193,635 was the result of trades necessitated by creation and redemption activity. The increase in the total commissions accrued to brokers by USCI for the nine months ended September 30, 2013 as compared to the nine months ended September 30, 2012 was primarily due to an increase in the number of contracts traded during the rebalancing periods for the nine months ended September 30, 2013. As an annualized percentage of average total net assets, USCI’s figure for the nine months ended September 30, 2013 represents approximately 0.07% of USCI’s average total net assets. By comparison, USCI’s figure for the nine months ended September 30, 2012 represented approximately 0.07% of USCI’s average total net assets. However, there can be no assurance that commission costs and portfolio turnover will not cause commission expenses to rise in future quarters.

	During the nine months ended September 30, 2013, total commissions accrued to brokers amounted to $549 for CPER. Of this amount, approximately $549 was a result of rebalancing costs and approximately $0 was the result of trades necessitated by creation and redemption activity for CPER. By comparison, during the nine months ended September 30, 2012, total commissions accrued to brokers amounted to $597 for CPER. Of this amount, approximately $439 was a result of rebalancing costs and approximately $158 was the result of trades necessitated by creation and redemption activity for CPER. The decrease in CPER’s total commissions accrued to brokers for the nine months ended September 30, 2013 as compared to the nine months ended September 30, 2012, was primarily due to a decrease in the total number of contracts traded during the nine months ended September 30, 2013. As an annualized percentage of average total net assets, CPER’s figure for the nine months ended September 30, 2013 represents approximately 0.03% of CPER’s average total net assets. By comparison, CPER’s figure for the nine months ended September 30, 2012 represented approximately 0.03% of CPER’s average total net assets. However, there can be no assurance that commission costs and portfolio turnover will not cause commission expenses to rise in future quarters.

	During the nine months ended September 30, 2013, total commissions accrued to brokers amounted to $1,524 for USAG. Of this amount, approximately $1,524 was a result of rebalancing costs and approximately $0 was the result of trades necessitated by creation and redemption activity for USAG. By comparison, during the nine months ended September 30, 2012, total commissions accrued to brokers amounted to $2,074 for USAG. Of this amount, approximately $1,379 was a result of rebalancing costs and approximately $695 was the result of trades necessitated by creation and redemption activity. As an annualized percentage of average daily total net assets, USAG’s figure for the nine months ended September 30, 2013 represents approximately 0.08% of USAG’s average daily total net assets. By comparison, USAG’s figure for the nine months ended September 30, 2012 represented approximately 0.14% of USAG’s average total net assets. However, there can be no assurance that commission costs and portfolio turnover will not cause commission expenses to rise in future quarters.

	During the nine months ended September 30, 2013, total commissions accrued to brokers amounted to $643 for USMI. Of this amount, approximately $546 was a result of rebalancing costs and approximately $97 was the result of trades necessitated by creation and redemption activity for USMI. By comparison, during the nine months ended September 30, 2012, total commissions accrued to brokers amounted to $476 for USMI. Of this amount, approximately $122 was a result of rebalancing costs and approximately $354 was the result of trades necessitated by creation and redemption activity. As an annualized percentage of average daily total net assets, USMI’s figure for the nine months ended September 30, 2013 represents approximately 0.03% of USMI’s average daily total net assets. By comparison, USMI’s figure for the nine months ended September 30, 2012 represented approximately 0.06% of USMI’s average daily total net assets. However, there can be no assurance that commission costs and portfolio turnover will not cause commission expenses to rise in future quarters.

	USCF is party to an Amended Advisory Agreement, dated July 1, 2011, as amended from time to time, with SummerHaven, whereby SummerHaven provides advisory services to USCF with respect to the Applicable Index for each Trust Series and investment decisions for each Trust Series. SummerHaven’s advisory services include, but are not limited to, general consultation regarding the calculation and maintenance of the Applicable Index for each Trust Series, anticipated changes to each Applicable Index and the nature of each Applicable Index’s current or anticipated component securities. For these services, USCF pays SummerHaven a fee based on a percentage of the average total net assets of each Trust Series . For USCI, the fee is equal to the percentage fees paid to USCF minus 0.14%, with that result multiplied by 0.5, minus 0.06% to arrive at the actual fee paid. For each of CPER, USAG and USMI, the fee is equal to the percentage fees paid to USCF minus 0.18%, with that result multiplied by 0.5, minus 0.06% to arrive at the actual fee paid.
	USCF is also party to an Amended Licensing Agreement, dated July 1, 2011, as amended from time to time, with SummerHaven, whereby SummerHaven sub-licensed to each Trust Series the use of certain names and marks, including the Applicable Index for each Trust Series for which SummerHaven has a sub-license from SummerHaven Indexing, the owner of each Applicable Index. Under the Licensing Agreement, USCF paid SummerHaven an annual fee of $15,000 per each Trust Series for the year ended December 31, 2012, plus an annual fee of 0.06% of the average daily total net assets of each Trust Series.

Financial_Instruments_Offbalan

Financial Instruments, Off-balance Sheet Risks and Contingencies	9 Months Ended
	Sep. 30, 2013
Risks and Uncertainties [Abstract]	'
Financial Instruments, Off-balance Sheet Risks and Contingencies	'
	NOTE 6 - FINANCIAL INSTRUMENTS, OFF-BALANCE SHEET RISKS AND CONTINGENCIES

	Each Trust Series engages in the trading of futures contracts and options on futures contracts and may engage in cleared swaps (collectively, “derivatives”). As such, each Trust Series is exposed to both market risk, which is the risk arising from changes in the market value of the contracts, and credit risk, which is the risk of failure by another party to perform according to the terms of a contract.

	Each Trust Series may enter into futures contracts and options on futures contracts to gain exposure to changes in the value of an underlying commodity. A futures contract obligates the seller to deliver (and the purchaser to accept) the future delivery of a specified quantity and type of a commodity at a specified time and place. Some futures contracts may call for physical delivery of the asset, while others are settled in cash. The contractual obligations of a buyer or seller may generally be satisfied by taking or making physical delivery of the underlying commodity or by making an offsetting sale or purchase of an identical futures contract on the same or linked exchange before the designated date of delivery.

	The purchase and sale of futures contracts and options on futures contracts require margin deposits with a futures commission merchant. Additional deposits may be necessary for any loss on contract value. The Commodity Exchange Act requires a futures commission merchant to segregate all customer transactions and assets from the futures commission merchant’s proprietary activities.

	Futures contracts involve, to varying degrees, elements of market risk (specifically commodity price risk) and exposure to loss in excess of the amount of variation margin. The face or contract amounts reflect the extent of the total exposure each Trust Series has in the particular classes of instruments. Additional risks associated with the use of futures contracts are an imperfect correlation between movements in the price of the futures contracts and the market value of the underlying securities and the possibility of an illiquid market for a futures contract.

	All of the Futures Contracts held by each Trust Series were exchange-traded through September 30, 2013. The risks associated with exchange-traded contracts are generally perceived to be less than those associated with over-the-counter transactions since, in over-the-counter transactions, a party must rely solely on the credit of its respective individual counterparties. However, in the future, if each Trust Series were to enter into non-exchange traded contracts, it would be subject to the credit risk associated with counterparty non-performance. The credit risk from counterparty non-performance associated with such instruments is the net unrealized gain, if any, on the transaction. Currently, each Trust Series has credit risk under its futures contracts since the sole counterparty to all domestic and foreign futures contracts is the clearinghouse for the exchange on which the relevant contracts are traded. In addition, each Trust Series bears the risk of financial failure by the clearing broker.

	A Trust Series’ cash and other property, such as Treasuries, deposited with a futures commission merchant are considered commingled with all other customer funds, subject to the futures commission merchant’s segregation requirements. In the event of a futures commission merchant’s insolvency, recovery may be limited to a pro rata share of segregated funds available. It is possible that the recovered amount could be less than the total of cash and other property deposited. The insolvency of a futures commission merchant could result in the complete loss of a Trust Series’ assets posted with that futures commission merchant; however, the majority of each Trust Series’ assets are held in Treasuries, cash and/or cash equivalents with the Trust Series’ custodian and would not be impacted by the insolvency of a futures commission merchant. The failure or insolvency of the Trust Series’ custodian, however, could result in a substantial loss of each Trust Series’ assets.

	USCF may invest a portion of each Trust Series’ cash in money market funds that seek to maintain a stable per unit NAV. Each Trust Series may be exposed to any risk of loss associated with an investment in such money market funds. As of September 30, 2013 and December 31, 2012, none of the Trust Series held investments in money market funds. Each Trust Series holds cash deposits with its custodian. Pursuant to a written agreement with BBH&Co., uninvested overnight cash balances are swept to offshore branches of U.S. regulated and domiciled banks located in Toronto, Canada, London, United Kingdom, Grand Cayman, Cayman Islands and Nassau, Bahamas which are subject to U.S. regulation and regulatory oversight. As of September 30, 2013 and December 31, 2012, USCI held cash deposits and investments in Treasuries in the amounts of $547,413,165 and $491,119,704, respectively, with the custodian and futures commission merchant. As of September 30, 2013 and December 31, 2012, CPER held cash deposits and investments in Treasuries in the amounts of $2,240,330 and $2,541,590, respectively, with the custodian and futures commission merchant. As of September 30, 2013 and December 31, 2012, USAG held cash deposits and investments in Treasuries in the amounts of $2,407,604 and $2,679,845, respectively, with the custodian and futures commission merchant. As of September 30, 2013 and December 31, 2012, USMI held cash deposits and investments in Treasuries in the amounts of $2,307,151 and $2,605,049, respectively, with the custodian and futures commission merchant. Some or all of these amounts may be subject to loss should the Trust Series’ custodian and/or futures commission merchant cease operations.

	For derivatives, risks arise from changes in the market value of the contracts. Theoretically, each Trust Series is exposed to market risk equal to the value of Futures Contracts purchased and unlimited liability on such contracts sold short. As both a buyer and a seller of options, each Trust Series pays or receives a premium at the outset and then bears the risk of unfavorable changes in the price of the contract underlying the option.

	The Trust Series’ policy is to continuously monitor its exposure to market and counterparty risk through the use of a variety of financial, position and credit exposure reporting controls and procedures. In addition, the Trust Series or USCF have a policy of requiring review of the credit standing of each broker or counterparty with which they conduct business.

	The financial instruments held by the applicable Trust Series are reported in its condensed statements of financial condition at market or fair value, or at carrying amounts that approximate fair value, because of their highly liquid nature and short-term maturity.

Financial_Highlights

Financial Highlights	9 Months Ended
Financial Highlights	Sep. 30, 2013
Financial Highlights [Abstract]	'
Financial Highlights	'
	The following tables present per unit performance data and other supplemental financial data for each Trust Series for the nine months ended September 30, 2013 and 2012 for the unitholders. This information has been derived from information presented in the condensed financial statements.

	USCI

			For the nine months ended				For the nine months ended
			September 30, 2013				September 30, 2012
			(Unaudited)				(Unaudited)
	Per Unit Operating Performance:
	Net asset value, beginning of period		$	58.45			$	58.47
	Total income (loss)			-1.81				3.41
	Total expenses			-0.48				-0.53
	Net increase (decrease) in net asset value			-2.29				2.88
	Net asset value, end of period		$	56.16			$	61.35

	Total Return			-3.92	%			4.93	%

	Ratios to Average Net Assets
	Total income (loss)			-3.3	%			4.63	%
	Expenses excluding management fees*			0.19	%			0.22	%
	Management fees*			0.95	%			0.95	%
	Net income (loss)			-4.16	%			3.75	%

	*	Annualized.

	CPER

		For the nine months ended			For the nine months ended
		September 30, 2013			September 30, 2012
		(Unaudited)			(Unaudited)
	Per Unit Operating Performance:
	Net asset value, beginning of period	$	25.43		$	24.47
	Total income (loss)		-2.66			2.02
	Total expenses		-0.15			-0.19
	Net increase (decrease) in net asset value		-2.81			1.83
	Net asset value, end of period	$	22.62		$	26.3

	Total Return		-11.05	%		7.48	%

	Ratios to Average Net Assets
	Total income (loss)		-11.47	%		8.5	%
	Management fees*		0.65	%**		0.82	%**
	Total expenses excluding management fees*		4.07	%		3.56	%
	Expenses waived*		-3.87	%		-3.38	%
	Net expenses excluding management fees*		0.2	%		0.18	%
	Net income (loss)		-12.11	%		7.75	%

	*	Annualized.
	**	Effective as of May 29, 2012 (and continuing at least through May 1, 2014), USCF voluntarily agreed to waive the management fee paid by CPER from 0.95% to 0.65% per annum of average daily total net assets.

	USAG

			For the nine months ended				For the nine months ended
			September 30, 2013				September 30, 2012
			(Unaudited)				(Unaudited)*
	Per Unit Operating Performance:
	Net asset value, beginning of period		$	25.56			$	25
	Total income (loss)			-1.7				2.51
	Total expenses			-0.19				-0.13
	Net increase (decrease) in net asset value			-1.89				2.38
	Net asset value, end of period		$	23.67			$	27.38

	Total Return			-7.39	%			9.52	%

Ratios to Average Net Assets
Total income (loss)			-7.03	%			12.58	%
Management fees**			0.8	%***			0.84	%***
Total expenses excluding management fees**			4.54	%			3.5	%
Expenses waived**			-4.28	%			-3.22	%
Net expenses excluding management fees**			0.25	%			0.28	%
Net income (loss)			-7.82	%			12.06	%

*	USAG commenced operations on April 13, 2012.
**	Annualized.
***	Effective as of May 29, 2012 (and continuing at least through May 1, 2014), USCF voluntarily agreed to waive the management fee paid by USAG from 0.95% to 0.80% per annum of average daily total net assets.

USMI

		For the nine months ended				For the nine months ended
		September 30, 2013				September 30, 2012
		(Unaudited)				(Unaudited)*
Per Unit Operating Performance:
Net asset value, beginning of period		$	26.47			$	25
Total income (loss)			-3.55				2.73
Total expenses			-0.16				-0.06
Net increase (decrease) in net asset value			-3.71				2.67
Net asset value, end of period		$	22.76			$	27.67

Total Return			-14.02	%			10.68	%

Ratios to Average Net Assets
Total income (loss)			-11.74	%			10.21	%
Management fees**			0.7	%***			0.7	%***
Total expenses excluding management fees**			4.14	%			3.56	%
Expenses waived**			-3.94	%			-3.38	%
Net expenses excluding management fees**			0.2	%			0.18	%
Net income (loss)			-12.42	%			9.96	%


*	USMI commenced operations on June 19, 2012.
**	Annualized.
***	Effective as of May 30, 2012 (and continuing at least through May 1, 2014), USCF voluntarily agreed to waive the management fee paid by USMI from 0.95% to 0.70% per annum of average daily total net assets. The reduced fee became operational as of June 19, 2012.

Total returns are calculated based on the change in value during the period. An individual unitholder’s total return and ratio may vary from the above total returns and ratios based on the timing of contributions to and withdrawals from each Trust Series.

Fair_Value_of_Financial_Instru

Fair Value of Financial Instruments

9 Months Ended

Sep. 30, 2013

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

NOTE 8 — FAIR VALUE OF FINANCIAL INSTRUMENTS

The Trust and each Trust Series value their investments in accordance with Accounting Standards Codification 820 – Fair Value Measurements and Disclosures (“ASC 820”). ASC 820 defines fair value, establishes a framework for measuring fair value in generally accepted accounting principles, and expands disclosures about fair value measurement. The changes to past practice resulting from the application of ASC 820 relate to the definition of fair value, the methods used to measure fair value, and the expanded disclosures about fair value measurement. ASC 820 establishes a fair value hierarchy that distinguishes between: (1) market participant assumptions developed based on market data obtained from sources independent of the Trust and each Trust Series (observable inputs) and (2) the Trust’s and each Trust Series’ own assumptions about market participant assumptions developed based on the best information available under the circumstances (unobservable inputs). The three levels defined by the ASC 820 hierarchy are as follows:

Level I – Quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date.

Level II – Inputs other than quoted prices included within Level I that are observable for the asset or liability, either directly or indirectly. Level II assets include the following: quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability, and inputs that are derived principally from or corroborated by observable market data by correlation or other means (market-corroborated inputs).

Level III – Unobservable pricing input at the measurement date for the asset or liability. Unobservable inputs shall be used to measure fair value to the extent that observable inputs are not available.

In some instances, the inputs used to measure fair value might fall within different levels of the fair value hierarchy. The level in the fair value hierarchy within which the fair value measurement in its entirety falls shall be determined based on the lowest input level that is significant to the fair value measurement in its entirety.

The following table summarizes the valuation of USCI’s securities at September 30, 2013 using the fair value hierarchy:

At September 30, 2013

Total

Level I

Level II

Level III

Short-Term Investments

345,168,420

—

Exchange-Traded Futures Contracts

Foreign Contracts

-1,675,599

—

United States Contracts

2,467,721

—

During the nine months ended September 30, 2013, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USCI’s securities at December 31, 2012 using the fair value hierarchy:

At December 31, 2012

Total

Level I

Level II

Level III

Short-Term Investments

435,149,105

—

Exchange-Traded Futures Contracts

Foreign Contracts

2,901,485

—

United States Contracts

-8,122,385

—

During the year ended December 31, 2012, there were no transfers between Level I and Level II.

The following table summarizes the valuation of CPER’s securities at September 30, 2013 using the fair value hierarchy:

At September 30, 2013

Total

Level I

Level II

Level III

Short-Term Investments

1,299,865

—

Exchange-Traded Futures Contracts

United States Contracts

25,075

—

During the nine months ended September 30, 2013, there were no transfers between Level I and Level II.

The following table summarizes the valuation of CPER’s securities at December 31, 2012 using the fair value hierarchy:

At December 31, 2012

Total

Level I

Level II

Level III

Short-Term Investments

2,149,689

—

Exchange-Traded Futures Contracts

United States Contracts

6,575

—

During the year ended December 31, 2012, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USAG’s securities at September 30, 2013 using the fair value hierarchy:

At September 30, 2013

Total

Level I

Level II

Level III

Short-Term Investments

1,249,883

—

Exchange-Traded Futures Contracts

Foreign Contracts

26,546

—

United States Contracts

-62,474

—

During the nine months ended September 30, 2013, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USAG’s securities at December 31, 2012 using the fair value hierarchy:

At December 31, 2012

Total

Level I

Level II

Level III

Short-Term Investments

2,199,688

—

Exchange-Traded Futures Contracts

Foreign Contracts

-31,470

—

United States Contracts

-87,685

—

During the year ended December 31, 2012, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USMI’s securities at September 30, 2013 using the fair value hierarchy:

At September 30, 2013

Total

Level I

Level II

Level III

Short-Term Investments

1,549,823

—

Exchange-Traded Futures Contracts

Foreign Contracts

-12,742

—

United States Contracts

-14,453

—

During the nine months ended September 30, 2013, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USMI’s securities at December 31, 2012 using the fair value hierarchy:

At December 31, 2012

Total

Level I

Level II

Level III

Short-Term Investments

2,349,792

—

Exchange-Traded Futures Contracts

Foreign Contracts

77,393

—

United States Contracts

-31,335

—

During the year ended December 31, 2012 there were no transfers between Level I and Level II.

The Trust and each Trust Series have adopted the provisions of Accounting Standards Codification 815 – Derivatives and Hedging, which require presentation of qualitative disclosures about objectives and strategies for using derivatives, quantitative disclosures about fair value amounts and gains and losses on derivatives.

Fair Value of Derivative Instruments Held by USCI

Derivatives not

Condensed

Fair Value

Accounted for

Statements of Financial

At September 30, 2013

At December 31, 2012

as Hedging

Condition Location

Instruments

Futures - Commodity Contracts

Assets

792,122

-5,220,900

Fair Value of Derivative Instruments Held by CPER

Derivatives not

Condensed

Fair Value

Accounted for

Statements of Financial

At September 30, 2013

At December 31, 2012

as Hedging

Condition Location

Instruments

Futures - Commodity Contracts

Assets

25,075

6,575

Fair Value of Derivative Instruments Held by USAG

Derivatives not

Condensed

Fair Value

Accounted for

Statements of Financial

At September 30, 2013

At December 31, 2012

as Hedging

Condition Location

Instruments

Futures - Commodity Contracts

Assets

-35,928

-119,155

Fair Value of Derivative Instruments Held by USMI

Derivatives not

Condensed

Fair Value

Accounted for

Statements of Financial

At September 30, 2013

At December 31, 2012

as Hedging

Condition Location

Instruments

Futures - Commodity Contracts

Assets

-27,195

46,058

The Effect of Derivative Instruments on the Condensed Statements of Operations of USCI

For the nine months ended

September 30, 2013

September 30, 2012

Derivatives not

Location of

Realized

Change in

Realized

Change in

Accounted for

Gain or (Loss)

Unrealized

Gain or (Loss)

Unrealized

as Hedging

on Derivatives

Gain or (Loss)

on Derivatives

Gain or (Loss)

Instruments

Recognized in

on Derivatives

Recognized in

on Derivatives

Income

Recognized in

Income

Recognized in

Income

Futures -

Realized loss on closed positions

-23,085,330

-12,231,495

Commodity Contracts

Change in unrealized gain on open positions

6,013,022

31,016,267

The Effect of Derivative Instruments on the Condensed Statements of Operations of CPER

For the nine months ended

September 30, 2013

September 30, 2012

Derivatives not

Location of

Realized

Change in

Realized

Change in

Accounted for

Gain or (Loss)

Unrealized

Gain or (Loss)

Unrealized

as Hedging

on Derivatives

Gain or (Loss)

on Derivatives

Gain or (Loss)

Instruments

Recognized in

on Derivatives

Recognized in

on Derivatives

Income

Recognized in

Income

Recognized in

Income

Futures -

Realized loss on closed positions

-285,950

-63,313

Commodity Contracts

Change in unrealized gain (loss) on open positions

18,500

278,838

The Effect of Derivative Instruments on the Condensed Statements of Operations of USAG

For the nine months ended

September 30, 2013

September 30, 2012*

Derivatives not

Location of

Realized

Change in

Realized

Change in

Accounted for

Gain or (Loss)

Unrealized

Gain or (Loss)

Unrealized

as Hedging

on Derivatives

Gain or (Loss)

on Derivatives

Gain or (Loss)

Instruments

Recognized in

on Derivatives

Recognized in

on Derivatives

Income

Recognized in

Income

Recognized in

Income

Futures -

Realized gain (loss) on closed positions

-253,247

368,209

Commodity Contracts

Change in unrealized gain on open positions

83,227

18,483

* USAG commenced operations on April 13, 2012.

The Effect of Derivative Instruments on the Condensed Statements of Operations of USMI

For the nine months ended

September 30, 2013

September 30, 2012*

Derivatives not

Location of

Realized

Change in

Realized

Change in

Accounted for

Gain or (Loss)

Unrealized

Gain or (Loss)

Unrealized

as Hedging

on Derivatives

Gain or (Loss)

on Derivatives

Gain or (Loss)

Instruments

Recognized in

on Derivatives

Recognized in

on Derivatives

Income

Recognized in

Income

Recognized in

Income

Futures -

Realized gain (loss) on closed positions

-236,824

132,421

Commodity Contracts

Change in unrealized gain (loss) on open positions

-73,253

175,713

* USMI commenced operations on June 19, 2012.

Subsequent_Events

Subsequent Events	9 Months Ended
Subsequent Events	Sep. 30, 2013
Subsequent Events [Abstract]	'
Subsequent Events	'
	NOTE 9 – SUBSEQUENT EVENTS

	The Trust and each Trust Series have performed an evaluation of subsequent events through the date the condensed financial statements were issued. As such, the evaluation resulted in the following amendments to disclosure, but such amendments had no impact to the financial statements.

	Mr. Adam Dunsby, a partner at SummerHaven, gave his notice to leave SummerHaven effective September 30, 2013. Beginning October 1, 2013, Dr. Geert Rouwenhorst assumed full responsibility for research and quantitative modeling, with the assistance of other SummerHaven staff. USCF does not anticipate Mr. Dunsby’s departure to have an impact on SummerHaven’s operations.

	With Mr. Dunsby’s departure, the “Principals of SummerHaven” disclosure found in the annual report on Form 10-K for the year ended December 31, 2012, filed on March 13, 2013, has been as amended as follows:

	Principals of SummerHaven

	Adam W. Dunsby had been employed by SummerHaven and was a partner of SummerHaven from April 2009 through September 30, 2013. Until September 30, 2013, Mr. Dunsby’s duties included quantitative modeling and portfolio construction. From April 1995 to April 2008, Mr. Dunsby was employed by Cornerstone Quantitative Investment Group Inc., a quantitative global macro CTA, as a co-founder and manager. Mr. Dunsby was not employed from April 2008 to April 2009. Mr. Dunsby was listed as a principal of SummerHaven from October 1, 2009 to September 30, 2013, as an associated person of SummerHaven from October 9, 2009 to September 30, 2013 and as an associate member of the NFA from October 9, 2009 to September 30, 2013. Mr. Dunsby graduated summa cum laude from the Wharton School of the University of Pennsylvania in 1990 with a BS in economics. He earned his PhD in Finance from Wharton in 1995. Mr. Dunsby is 45 years old.

Summary_Of_Significant_Account1

Summary Of Significant Accounting Policies (Policies)	9 Months Ended
Summary Of Significant Accounting Policies (Policies)	Sep. 30, 2013
Offsetting Liabilities [Line Items]	'
Revenue Recognition	'
	Revenue Recognition

	Commodity futures contracts, forward contracts, physical commodities, and related options are recorded on the trade date. All such transactions are recorded on the identified cost basis and marked to market daily. Unrealized gains or losses on open contracts are reflected in the condensed statements of financial condition and represent the difference between the original contract amount and the market value (as determined by exchange settlement prices for futures contracts and related options and cash dealer prices at a predetermined time for forward contracts, physical commodities, and their related options) as of the last business day of the year or as of the last date of the condensed financial statements. Changes in the unrealized gains or losses between periods are reflected in the condensed statements of operations. Each Trust Series earns interest on its assets denominated in U.S. dollars on deposit with the futures commission merchant at the 90-day Treasury bill rate. In addition, each Trust Series earns income on funds held at the custodian and/or futures commission merchant at prevailing market rates earned on such investments.

Brokerage Commissions	'
	Brokerage Commissions

	Brokerage commissions on all open commodity futures contracts are accrued on a full-turn basis.

Income Taxes	'
	Income Taxes

	The Trust Series are not subject to federal income taxes; each investor reports his/her allocable share of income, gain, loss deductions or credits on his/her own income tax return.

	In accordance with accounting principles generally accepted in the United States of America (“GAAP”), each Trust Series is required to determine whether a tax position is more likely than not to be sustained upon examination by the applicable taxing authority, including resolution of any tax related appeals or litigation processes, based on the technical merits of the position. Each Trust Series files an income tax return in the U.S. federal jurisdiction, and may file income tax returns in various U.S. states. None of the Trust Series is subject to income tax return examinations by major taxing authorities for years before 2010 (year of the Trust Series’ inception, but not necessarily the commencement of operations for each Trust Series). The tax benefit recognized is measured as the largest amount of benefit that has a greater than fifty percent likelihood of being realized upon ultimate settlement. De-recognition of a tax benefit previously recognized results in each Trust Series recording a tax liability that reduces net assets. However, each Trust Series’ conclusions regarding this policy may be subject to review and adjustment at a later date based on factors including, but not limited to, on-going analysis of and changes to tax laws, regulations and interpretations thereof. Each Trust Series recognizes interest accrued related to unrecognized tax benefits and penalties related to unrecognized tax benefits in income tax fees payable, if assessed. No interest expense or penalties have been recognized as of and for the period ended September 30, 2013 for any Trust Series.

Trust Capital and Allocation of Income and Losses	'
	Trust Capital and Allocation of Income and Losses

	Profit or loss shall be allocated among the unitholders of each Trust Series in proportion to the number of units each investor holds as of the close of each month. USCF may revise, alter or otherwise modify this method of allocation as described in the Trust Agreement.

Adoption of New Monthly Allocation Convention	'
	Adoption of New Monthly Allocation Convention

	Effective January 1, 2012, USCI adopted a new convention for allocating items of income, gain, loss, deduction and credits. In situations where a partner’s interest in a partnership is sold or otherwise transferred during a taxable year, the Code generally requires that partnership tax items for the year be allocated among the partners using either an interim closing of the books or a daily proration method. USCI uses an interim closing of the books method under which income, gains and losses (both realized and unrealized), deductions and credits are determined on a monthly basis. Prior to January 1, 2012, USCI allocated these tax items among the holders of the units (including those who dispose of units during a taxable year) in proportion to the number of units owned by them on the last trading day of each month. For this purpose, if an investor holds a unit as of the close of business of the last trading day of a particular month, such investor is treated as if it owned the unit throughout the month and thus is allocated all of the items of income, gain, deduction, loss or credit attributable to that unit for such month (the “same-month convention”).

	Effective January 1, 2012 for USCI, November 15, 2011 for CPER, April 13, 2012 for USAG and June 19, 2012 for USMI, an allocation convention is applied pursuant to which each Trust Series’ tax items for each month will be allocated among the holders of units in proportion to the number of units owned by them as of the close of business of the last trading day of the previous month. If an investor who holds a unit as of the close of business on the last trading day of the previous month disposes of a unit during the current month, such investor will be treated for purposes of making allocations as if it owned the unit throughout the current month (the “next-month convention”). For example, an investor who buys a unit on April 10 of a year and sells it on May 20 of the same year will be allocated all of the tax items attributable to May (because he or she is deemed to hold it through the last day of May) but will not be allocated any of the tax items attributable to April. The tax items attributable to that unit for April will be allocated to the person who is the actual or deemed holder of the unit as of the close of business on the last trading day of March.

	For investors in USCI, as a result of the transition from the same-month convention to the next-month convention, an investor who bought a unit in December 2011 and sold the unit on or after January 1, 2012 will be allocated the tax items attributable to that unit for December 2011 as well as the tax items attributable to that unit for 2012.

Creations and Redemptions	'
	Creations and Redemptions

	Effective as of May 1, 2012, Authorized Purchasers may purchase Creation Baskets or redeem Redemption Baskets for USCI, CPER and USAG only in blocks of 50,000 units at a price equal to the NAV of the units calculated shortly after the close of the core trading session on the NYSE Arca on the day the order is placed. Prior to May 1, 2012, Authorized Purchasers could only purchase Creation Baskets or redeem Redemption Baskets for USCI, CPER and USAG in blocks of 100,000 units. USMI was not available to the public until June 19, 2012, and from its inception of offering, Authorized Purchasers could only purchase Creation Baskets in blocks of 50,000 units.

	Each Trust Series receives or pays the proceeds from units sold or redeemed within three business days after the trade date of the purchase or redemption. The amounts due from Authorized Purchasers are reflected in each Trust Series’ condensed statements of financial condition as receivable for units sold, and amounts payable to Authorized Purchasers upon redemption are reflected as payable for units redeemed.

Calculation of Net Asset Value Per Unit	'
	Calculation of Net Asset Value Per Unit

	Each Trust Series’ per unit NAV is calculated on each NYSE Arca trading day by taking the current market value of its total assets, subtracting any liabilities and dividing the amount by the total number of units outstanding. Each Trust Series uses the closing prices on the relevant Futures Exchanges (as defined in Note 3 below) of the Applicable Benchmark Component Futures Contracts (as defined in Note 3 below) that at any given time make up the Applicable Index (as defined in Note 3 below) (determined at the earlier of the close of such exchange or 2:30 p.m. New York time) for the contracts traded on the Futures Exchanges, but calculates or determines the value of all other investments of each Trust Series using market quotations, if available, or other information customarily used to determine the fair value of such investments.

Net Income (Loss) Per Unit	'
	Net Income (Loss) Per Unit

	Net income (loss) per unit is the difference between the per unit NAV at the beginning of each period and the per unit NAV at the end of each period. The weighted average number of units outstanding was computed for purposes of disclosing net income (loss) per weighted average unit. The weighted average units are equal to the number of units outstanding at the end of the period, adjusted proportionately for units added and redeemed based on the amount of time the units were outstanding during such period. As of September 30, 2013, USCF held 5 units of USMI. As of September 30, 2013, USCF held 5 units of USCI, held 40 units of CPER and held 5 units of USAG.

Offering Costs	'
	Offering Costs

	Offering costs incurred in connection with the registration of units prior to the commencement of the offering are borne by USCF. Offering costs incurred in connection with the registration of additional units after the commencement of the offering are borne by each Trust Series. These costs include registration fees paid to regulatory agencies and all legal, accounting, printing and other expenses associated with such offerings. Costs borne by the Trust Series after the commencement of an offering are accounted for as a deferred charge and thereafter amortized to expense over twelve months on a straight-line basis or a shorter period if warranted.

Cash Equivalents	'
	Cash Equivalents

	Cash equivalents include money market funds and overnight deposits or time deposits with original maturity dates of six months or less.

Use of Estimates	'
	Use of Estimates

	The preparation of condensed financial statements in conformity with GAAP requires USCF to make estimates and assumptions that affect the reported amount of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed financial statements, and the reported amounts of the revenue and expenses during the reporting period. Actual results may differ from those estimates and assumptions.

Financial_Highlights_Tables

Financial Highlights (Tables)	9 Months Ended
Financial Highlights (Tables)	Sep. 30, 2013
Financial Highlights [Abstract]	'
Per Unit Performance Data and Other Supplemental Financial Data for Usci, Cper, Usag and Usmi	'
	The following tables present per unit performance data and other supplemental financial data for each Trust Series for the nine months ended September 30, 2013 and 2012 for the unitholders. This information has been derived from information presented in the condensed financial statements.

	USCI

			For the nine months ended				For the nine months ended
			September 30, 2013				September 30, 2012
			(Unaudited)				(Unaudited)
	Per Unit Operating Performance:
	Net asset value, beginning of period		$	58.45			$	58.47
	Total income (loss)			-1.81				3.41
	Total expenses			-0.48				-0.53
	Net increase (decrease) in net asset value			-2.29				2.88
	Net asset value, end of period		$	56.16			$	61.35

	Total Return			-3.92	%			4.93	%

	Ratios to Average Net Assets
	Total income (loss)			-3.3	%			4.63	%
	Expenses excluding management fees*			0.19	%			0.22	%
	Management fees*			0.95	%			0.95	%
	Net income (loss)			-4.16	%			3.75	%

	*	Annualized.

	CPER

		For the nine months ended			For the nine months ended
		September 30, 2013			September 30, 2012
		(Unaudited)			(Unaudited)
	Per Unit Operating Performance:
	Net asset value, beginning of period	$	25.43		$	24.47
	Total income (loss)		-2.66			2.02
	Total expenses		-0.15			-0.19
	Net increase (decrease) in net asset value		-2.81			1.83
	Net asset value, end of period	$	22.62		$	26.3

	Total Return		-11.05	%		7.48	%

	Ratios to Average Net Assets
	Total income (loss)		-11.47	%		8.5	%
	Management fees*		0.65	%**		0.82	%**
	Total expenses excluding management fees*		4.07	%		3.56	%
	Expenses waived*		-3.87	%		-3.38	%
	Net expenses excluding management fees*		0.2	%		0.18	%
	Net income (loss)		-12.11	%		7.75	%

	*	Annualized.
	**	Effective as of May 29, 2012 (and continuing at least through May 1, 2014), USCF voluntarily agreed to waive the management fee paid by CPER from 0.95% to 0.65% per annum of average daily total net assets.

	USAG

			For the nine months ended				For the nine months ended
			September 30, 2013				September 30, 2012
			(Unaudited)				(Unaudited)*
	Per Unit Operating Performance:
	Net asset value, beginning of period		$	25.56			$	25
	Total income (loss)			-1.7				2.51
	Total expenses			-0.19				-0.13
	Net increase (decrease) in net asset value			-1.89				2.38
	Net asset value, end of period		$	23.67			$	27.38

	Total Return			-7.39	%			9.52	%

Ratios to Average Net Assets
Total income (loss)			-7.03	%			12.58	%
Management fees**			0.8	%***			0.84	%***
Total expenses excluding management fees**			4.54	%			3.5	%
Expenses waived**			-4.28	%			-3.22	%
Net expenses excluding management fees**			0.25	%			0.28	%
Net income (loss)			-7.82	%			12.06	%

*	USAG commenced operations on April 13, 2012.
**	Annualized.
***	Effective as of May 29, 2012 (and continuing at least through May 1, 2014), USCF voluntarily agreed to waive the management fee paid by USAG from 0.95% to 0.80% per annum of average daily total net assets.

USMI

		For the nine months ended				For the nine months ended
		September 30, 2013				September 30, 2012
		(Unaudited)				(Unaudited)*
Per Unit Operating Performance:
Net asset value, beginning of period		$	26.47			$	25
Total income (loss)			-3.55				2.73
Total expenses			-0.16				-0.06
Net increase (decrease) in net asset value			-3.71				2.67
Net asset value, end of period		$	22.76			$	27.67

Total Return			-14.02	%			10.68	%

Ratios to Average Net Assets
Total income (loss)			-11.74	%			10.21	%
Management fees**			0.7	%***			0.7	%***
Total expenses excluding management fees**			4.14	%			3.56	%
Expenses waived**			-3.94	%			-3.38	%
Net expenses excluding management fees**			0.2	%			0.18	%
Net income (loss)			-12.42	%			9.96	%


*	USMI commenced operations on June 19, 2012.
**	Annualized.
***	Effective as of May 30, 2012 (and continuing at least through May 1, 2014), USCF voluntarily agreed to waive the management fee paid by USMI from 0.95% to 0.70% per annum of average daily total net assets. The reduced fee became operational as of June 19, 2012.

Fair_Value_of_Financial_Instru1

Fair Value of Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2013

Fair Value Disclosures [Abstract]

Valuation of Usci's, Cper's, Usag's and Usmi's Securities Using Fair Value Hierarchy

The following table summarizes the valuation of USCI’s securities at September 30, 2013 using the fair value hierarchy:

At September 30, 2013

Total

Level I

Level II

Level III

Short-Term Investments

345,168,420

—

Exchange-Traded Futures Contracts

Foreign Contracts

-1,675,599

—

United States Contracts

2,467,721

—

During the nine months ended September 30, 2013, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USCI’s securities at December 31, 2012 using the fair value hierarchy:

At December 31, 2012

Total

Level I

Level II

Level III

Short-Term Investments

435,149,105

—

Exchange-Traded Futures Contracts

Foreign Contracts

2,901,485

—

United States Contracts

-8,122,385

—

During the year ended December 31, 2012, there were no transfers between Level I and Level II.

The following table summarizes the valuation of CPER’s securities at September 30, 2013 using the fair value hierarchy:

At September 30, 2013

Total

Level I

Level II

Level III

Short-Term Investments

1,299,865

—

Exchange-Traded Futures Contracts

United States Contracts

25,075

—

During the nine months ended September 30, 2013, there were no transfers between Level I and Level II.

The following table summarizes the valuation of CPER’s securities at December 31, 2012 using the fair value hierarchy:

At December 31, 2012

Total

Level I

Level II

Level III

Short-Term Investments

2,149,689

—

Exchange-Traded Futures Contracts

United States Contracts

6,575

—

During the year ended December 31, 2012, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USAG’s securities at September 30, 2013 using the fair value hierarchy:

At September 30, 2013

Total

Level I

Level II

Level III

Short-Term Investments

1,249,883

—

Exchange-Traded Futures Contracts

Foreign Contracts

26,546

—

United States Contracts

-62,474

—

During the nine months ended September 30, 2013, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USAG’s securities at December 31, 2012 using the fair value hierarchy:

At December 31, 2012

Total

Level I

Level II

Level III

Short-Term Investments

2,199,688

—

Exchange-Traded Futures Contracts

Foreign Contracts

-31,470

—

United States Contracts

-87,685

—

During the year ended December 31, 2012, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USMI’s securities at September 30, 2013 using the fair value hierarchy:

At September 30, 2013

Total

Level I

Level II

Level III

Short-Term Investments

1,549,823

—

Exchange-Traded Futures Contracts

Foreign Contracts

-12,742

—

United States Contracts

-14,453

—

During the nine months ended September 30, 2013, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USMI’s securities at December 31, 2012 using the fair value hierarchy:

At December 31, 2012

Total

Level I

Level II

Level III

Short-Term Investments

2,349,792

—

Exchange-Traded Futures Contracts

Foreign Contracts

77,393

—

United States Contracts

-31,335

—

Fair Value of Derivative Instruments Held by Usci, Cper, Usag and Usmi

Fair Value of Derivative Instruments Held by USCI

Derivatives not

Condensed

Fair Value

Accounted for

Statements of Financial

At September 30, 2013

At December 31, 2012

as Hedging

Condition Location

Instruments

Futures - Commodity Contracts

Assets

792,122

-5,220,900

Fair Value of Derivative Instruments Held by CPER

Derivatives not

Condensed

Fair Value

Accounted for

Statements of Financial

At September 30, 2013

At December 31, 2012

as Hedging

Condition Location

Instruments

Futures - Commodity Contracts

Assets

25,075

6,575

Fair Value of Derivative Instruments Held by USAG

Derivatives not

Condensed

Fair Value

Accounted for

Statements of Financial

At September 30, 2013

At December 31, 2012

as Hedging

Condition Location

Instruments

Futures - Commodity Contracts

Assets

-35,928

-119,155

Fair Value of Derivative Instruments Held by USMI

Derivatives not

Condensed

Fair Value

Accounted for

Statements of Financial

At September 30, 2013

At December 31, 2012

as Hedging

Condition Location

Instruments

Futures - Commodity Contracts

Assets

-27,195

46,058

Effect of Derivative Instruments on Statements of Operations of Usci, Cper, Usag and Usmi

The Effect of Derivative Instruments on the Condensed Statements of Operations of USCI

For the nine months ended

September 30, 2013

September 30, 2012

Derivatives not

Location of

Realized

Change in

Realized

Change in

Accounted for

Gain or (Loss)

Unrealized

Gain or (Loss)

Unrealized

as Hedging

on Derivatives

Gain or (Loss)

on Derivatives

Gain or (Loss)

Instruments

Recognized in

on Derivatives

Recognized in

on Derivatives

Income

Recognized in

Income

Recognized in

Income

Futures -

Realized loss on closed positions

-23,085,330

-12,231,495

Commodity Contracts

Change in unrealized gain on open positions

6,013,022

31,016,267

The Effect of Derivative Instruments on the Condensed Statements of Operations of CPER

For the nine months ended

September 30, 2013

September 30, 2012

Derivatives not

Location of

Realized

Change in

Realized

Change in

Accounted for

Gain or (Loss)

Unrealized

Gain or (Loss)

Unrealized

as Hedging

on Derivatives

Gain or (Loss)

on Derivatives

Gain or (Loss)

Instruments

Recognized in

on Derivatives

Recognized in

on Derivatives

Income

Recognized in

Income

Recognized in

Income

Futures -

Realized loss on closed positions

-285,950

-63,313

Commodity Contracts

Change in unrealized gain (loss) on open positions

18,500

278,838

The Effect of Derivative Instruments on the Condensed Statements of Operations of USAG

For the nine months ended

September 30, 2013

September 30, 2012*

Derivatives not

Location of

Realized

Change in

Realized

Change in

Accounted for

Gain or (Loss)

Unrealized

Gain or (Loss)

Unrealized

as Hedging

on Derivatives

Gain or (Loss)

on Derivatives

Gain or (Loss)

Instruments

Recognized in

on Derivatives

Recognized in

on Derivatives

Income

Recognized in

Income

Recognized in

Income

Futures -

Realized gain (loss) on closed positions

-253,247

368,209

Commodity Contracts

Change in unrealized gain on open positions

83,227

18,483

* USAG commenced operations on April 13, 2012.

The Effect of Derivative Instruments on the Condensed Statements of Operations of USMI

For the nine months ended

September 30, 2013

September 30, 2012*

Derivatives not

Location of

Realized

Change in

Realized

Change in

Accounted for

Gain or (Loss)

Unrealized

Gain or (Loss)

Unrealized

as Hedging

on Derivatives

Gain or (Loss)

on Derivatives

Gain or (Loss)

Instruments

Recognized in

on Derivatives

Recognized in

on Derivatives

Income

Recognized in

Income

Recognized in

Income

Futures -

Realized gain (loss) on closed positions

-236,824

132,421

Commodity Contracts

Change in unrealized gain (loss) on open positions

-73,253

175,713

* USMI commenced operations on June 19, 2012.

Organization_And_Business_Addi

Organization And Business (Additional Information) (Details)

Sep. 30, 2013

1-May-12

Jul. 01, 2011

Aug. 10, 2010

1-May-12

Sep. 30, 2013

1-May-12

Nov. 15, 2011

1-May-12

Sep. 30, 2013

1-May-12

Apr. 13, 2012

1-May-12

Sep. 30, 2013

Jun. 09, 2012

1-May-12

United States Commodity Index Fund [Member]

United States Copper Index Fund [Member]

United States Agriculture Index Fund [Member]

United States Metals Index Fund [Member]

Creation Baskets [Member]

Marketing Agent [Member]

Creation Baskets [Member]

Marketing Agent [Member]

Creation Baskets [Member]

Marketing Agent [Member]

Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]

Number of Units per basket

50,000

100,000

50,000

100,000

50,000

100,000

Fee paid by Authorized Purchasers for each order placed to create one or more Creation Baskets or to redeem one or more baskets

350

1,000

350

1,000

350

1,000

350

1,000

Summary_Of_Significant_Account2

Summary Of Significant Accounting Policies (Additional Information) (Details)	9 Months Ended
	Sep. 30, 2013	1-May-12
Significant Accounting Policies [Line Items]	'	'
Minimum likelihood of tax benefits being recognized upon ultimate settlement	50.00%	'
Cash equivalents maturity period	'6 years	'
United States Metals Index Fund [Member]	'	'
Significant Accounting Policies [Line Items]	'	'
Ending Balances (in units)	5	'
United States Commodity Index Fund [Member]	'	'
Significant Accounting Policies [Line Items]	'	'
Number of Units per basket	'	50,000
Ending Balances (in units)	5	'
United States Copper Index Fund [Member]	'	'
Significant Accounting Policies [Line Items]	'	'
Number of Units per basket	'	50,000
Ending Balances (in units)	40	'
United States Agriculture Index Fund [Member]	'	'
Significant Accounting Policies [Line Items]	'	'
Number of Units per basket	'	50,000
Ending Balances (in units)	5	'
Prior to May First Two Thousand Twelve [Member] \| United States Commodity Index Fund [Member]	'	'
Significant Accounting Policies [Line Items]	'	'
Number of Units per basket	100,000	'
Prior to May First Two Thousand Twelve [Member] \| United States Copper Index Fund [Member]	'	'
Significant Accounting Policies [Line Items]	'	'
Number of Units per basket	100,000	'
Prior to May First Two Thousand Twelve [Member] \| United States Agriculture Index Fund [Member]	'	'
Significant Accounting Policies [Line Items]	'	'
Number of Units per basket	100,000	'
Creation Baskets [Member]	'	'
Significant Accounting Policies [Line Items]	'	'
Number of Units per basket	50,000	'

Trust_Series_Additional_Inform

Trust Series (Additional Information) (Details) (USD $)

9 Months Ended

0 Months Ended

9 Months Ended

0 Months Ended

9 Months Ended

0 Months Ended

9 Months Ended

0 Months Ended

9 Months Ended

Sep. 30, 2013

Dec. 31, 2012

Aug. 10, 2010

Jul. 30, 2010

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2012

Dec. 31, 2011

Jul. 01, 2011

Nov. 10, 2010

Dec. 31, 2009

Sep. 30, 2013

Sep. 06, 2011

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2012

1-May-12

Apr. 13, 2012

Dec. 31, 2011

Nov. 10, 2010

Sep. 30, 2013

Sep. 06, 2011

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 09, 2012

1-May-12

Dec. 31, 2011

Nov. 10, 2010

Sep. 30, 2013

Nov. 15, 2011

Sep. 06, 2011

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2012

1-May-12

Dec. 31, 2011

Nov. 10, 2010

Sep. 30, 2013

United States Commodity Index Fund [Member]

United States Agriculture Index Fund [Member]

United States Metals Index Fund [Member]

United States Copper Index Fund [Member]

Futures Contracts [Member]

NYMEX [Member]

Ice Futures [Member]

Chicago Board of Trade [Member]

Chicago Mercantile Exchange [Member]

London Metal Exchange [Member]

Commodity Exchange Inc [Member]

Ice Futures [Member]

Chicago Board of Trade [Member]

Chicago Mercantile Exchange [Member]

Kansas City Board Of Trade [Member]

NYMEX [Member]

Chicago Mercantile Exchange [Member]

London Metal Exchange [Member]

Commodity Exchange Inc [Member]

Capital Unit [Line Items]

Sponsor capital contribution

$3,000

Capital contribution to trust series

1,000

Partner sponsor units description

'On November 14, 2011, USCF received 40 Sponsor Units of CPER in exchange for the previously received capital contribution, representing a beneficial interest in CPER. On December 7, 2011, USCF redeemed the 40 Sponsor Units of CPER and purchased 40 units of CPER in the open market. On April 13, 2012, USCF received 40 Sponsor Units of USAG in exchange for the previously received capital contribution, representing a beneficial interest in USAG. On June 28, 2012, USCF redeemed the 40 Sponsor Units of USAG and on October 3, 2012, purchased 5 units of USAG on the open market. On June 19, 2012, USCF received 40 Sponsor Units of USMI in exchange for the previously received capital contribution, representing a beneficial interest in USMI. On August 27, 2012, USCF redeemed the 40 Sponsor Units of USMI and, on September 4, 2013, purchased 5 units of USMI on the open market.

'In connection with the commencement of USCI’s initial offering of units, USCF received 20 Sponsor Units of USCI in exchange for the previously received capital contribution, representing a beneficial ownership interest in USCI.

Number of initially registered units on Form S-1 with the U.S. Securities and Exchange Commission

50,000,000

20,000,000

30,000,000

Commenced investment operations date

10-Aug-10

15-Nov-11

Initial offering price per unit NAV

$50

$56.16

$58.45

$61.35

$58.47

$23.67

$25.56

$27.38

[1]

$25

[1]

$22.76

$26.47

$27.67

[2]

$25

[2]

$25

$22.62

$25.43

$26.30

$24.47

Number of units issued

100,000

Value of unit issued

$5,000,000

$2,500,000

Number of registered units

100,000

Fee paid by Authorized Purchasers for each order placed to create one or more Creation Baskets or to redeem one or more baskets

1,000

350

1,000

350

1,000

350

1,000

350

1,000

Future contract held

14,844

2,660

2,816

936

2,312

5,643

477

[1]

USAG commenced operations on April 13, 2012.

[2]

USMI commenced operations on June 19, 2012.

Fees_Paid_By_Each_Trust_Series1

Fees Paid By Each Trust Series And Related Party Transactions (Additional Information) (Details) (USD $)

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

0 Months Ended

3 Months Ended

9 Months Ended

0 Months Ended

3 Months Ended

9 Months Ended

0 Months Ended

3 Months Ended

9 Months Ended

0 Months Ended

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

29-May-12

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

29-May-12

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

29-May-12

30-May-12

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

30-May-12

United States Commodity Index Fund [Member]

United States Copper Index Fund [Member]

United States Agriculture Index Fund [Member]

United States Metals Index Fund [Member]

Maximum [Member]

Fees Paid and Related Party Transactions [Line Items]

Percentage of average daily net assets paid monthly

0.95%

USCF Management Fee

'USCI, CPER, USAG and USMI is contractually obligated to pay USCF a fee, which is paid monthly, equal to 0.95% per annum of average daily total net assets

Percentage of waiver management fee

0.65%

3.87%

[1]

3.38%

[1]

0.95%

0.80%

4.28%

[1]

3.22%

[1],[2]

0.95%

0.70%

3.94%

[1]

3.38%

[1],[3]

0.95%

Trustee annual fee

$3,000

Noninterest Expense Directors Fees

560,625

Estimated investor tax reporting cost

400,000

60,000

Costs and expenses annual limit for reimbursement

0.15%

Expense waiver

$53,332

$75,671

$221,484

$140,801

$19,181

$23,656

$67,171

$64,905

$17,041

[4]

$26,019

[4]

$77,135

[4]

$46,719

[4]

$17,110

[5]

$25,996

[5]

$77,178

[5]

$29,177

[5]

[1]

Annualized.

[2]

USAG commenced operations on April 13, 2012.

[3]

USMI commenced operations on June 19, 2012.

[4]

The commencement of operations of the United States Agriculture Index Fund was April 13, 2012.

[5]

The commencement of operations of the United States Metals Index Fund was June 19, 2012.

Contracts_and_Agreements_Addit

Contracts and Agreements (Additional Information) (Details) (USD $)

3 Months Ended

9 Months Ended

12 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Licensing Agreements [Member]

United States Commodity Index Fund [Member]

United States Copper Index Fund [Member]

United States Agriculture Index Fund [Member]

United States Metals Index Fund [Member]

Maximum [Member]

Minimum [Member]

For the first $500 million [Member]

Combined net assets greater than $500 million but less than $1 billion [Member]

Combined net assets exceed $1 billion [Member]

Marketing Agreement [Member]

Rebalancing Investments Transaction [Member]

Trades Necessitated By Creation And Redemption Activity [Member]

Futures Contracts and options on Futures Contracts [Member]

Rebalancing Investments Transaction [Member]

Trades Necessitated By Creation And Redemption Activity [Member]

Rebalancing Investments Transaction [Member]

Trades Necessitated By Creation And Redemption Activity [Member]

Futures Contracts and options on Futures Contracts [Member]

Rebalancing Investments Transaction [Member]

Trades Necessitated By Creation And Redemption Activity [Member]

Futures Contracts and options on Futures Contracts [Member]

Maximum [Member]

Minimum [Member]

On each Trust Series' assets up to 3 billion [Member]

On each Trust Series' assets in excess of $3 billion [Member]

Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]

Fee percentage

0.06%

0.05%

0.04%

0.06%

0.04%

Base amount for determining fee percentage

$75,000

$500,000,000,000

$1,000,000,000

$500,000,000,000

$1,000,000,000

$3,000,000,000

Annual transfer agency services fee

20,000

Transaction fees per transaction

Commissions per round-turn trade, including applicable exchange and NFA fees for Futures Contracts and options on Futures Contracts

Brokerage commissions

82,737

90,010

286,855

227,355

81,812

88,340

284,139

224,208

275,996

30,573

8,143

193,635

149

278

549

597

549

439

158

510

[1]

1,098

[1]

1,524

[1]

2,074

[1]

1,524

1,379

695

266

[2]

294

[2]

643

[2]

476

[2]

546

122

354

Brokerage commissions as a percentage of average daily net assets

0.95%

0.07%

0.95%

0.08%

0.14%

0.95%

0.03%

0.06%

Annual licensing fee

$15,000

Management fee paid to SummerHaven by USCF

'. For USCI, the fee is equal to the percentage fees paid to USCF minus 0.14%, with that result multiplied by 0.5, minus 0.06% to arrive at the actual fee paid. For each of CPER, USAG and USMI, the fee is equal to the percentage fees paid to USCF minus 0.18%, with that result multiplied by 0.5, minus 0.06% to arrive at the actual fee paid.

[1]

The commencement of operations of the United States Agriculture Index Fund was April 13, 2012.

[2]

The commencement of operations of the United States Metals Index Fund was June 19, 2012.

Financial_Instruments_Offbalan1

Financial Instruments, Off-balance Sheet Risks and Contingencies (Additional Information) (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
United States Commodity Index Fund [Member]	'	'
Carrying Amounts and Fair Values of Financial Instruments or Liabilities [Line Items]	'	'
Cash deposits and investments in Treasuries	$547,413,165	$491,119,704
United States Copper Index Fund [Member]	'	'
Carrying Amounts and Fair Values of Financial Instruments or Liabilities [Line Items]	'	'
Cash deposits and investments in Treasuries	2,240,330	2,541,590
United States Agriculture Index Fund [Member]	'	'
Carrying Amounts and Fair Values of Financial Instruments or Liabilities [Line Items]	'	'
Cash deposits and investments in Treasuries	2,407,604	2,679,845
United States Metals Index Fund [Member]	'	'
Carrying Amounts and Fair Values of Financial Instruments or Liabilities [Line Items]	'	'
Cash deposits and investments in Treasuries	$2,307,151	$2,605,049

Financial_Highlights_Per_Unit_

Financial Highlights (Per Unit Performance Data and Other Supplemental Financial Data) (Details) (USD $)

9 Months Ended

0 Months Ended

9 Months Ended

0 Months Ended

9 Months Ended

0 Months Ended

9 Months Ended

Sep. 30, 2013

Sep. 30, 2012

Aug. 10, 2010

29-May-12

Sep. 30, 2013

Sep. 30, 2012

Nov. 15, 2011

29-May-12

Sep. 30, 2013

Sep. 30, 2012

Apr. 13, 2012

30-May-12

Sep. 30, 2013

Sep. 30, 2012

Jun. 09, 2012

United States Commodity Index Fund [Member]

United States Copper Index Fund [Member]

United States Agriculture Index Fund [Member]

United States Metals Index Fund [Member]

Increase Decrease In Partners Capital RollForward [Abstract]

Net asset value, beginning of period

$58.45

$58.47

$50

$25.43

$24.47

$25

$25.56

$25

[1]

$25

$26.47

$25

[2]

$25

Total income (loss)

($1.81)

$3.41

($2.66)

$2.02

($1.70)

$2.51

[1]

($3.55)

$2.73

[2]

Total expenses

($0.48)

($0.53)

($0.15)

($0.19)

($0.13)

[1]

($0.16)

($0.06)

[2]

Net increase (decrease) in net asset value

($2.29)

$2.88

($2.81)

$1.83

($1.89)

$2.38

[1]

($3.71)

$2.67

[2]

Net asset value, end of period

$56.16

$61.35

$50

$22.62

$26.30

$25

$23.67

$27.38

[1]

$25

$22.76

$27.67

[2]

$25

Total Return

-3.92%

4.93%

-11.05%

7.48%

-7.39%

9.52%

[1]

-14.02%

10.68%

[2]

Ratios to Average Net Assets

Total income (loss)

-3.30%

4.63%

-11.47%

8.50%

-7.03%

12.58%

[1]

-11.74%

10.21%

[2]

Management fees

0.95%

[3]

0.95%

[3]

0.65%

[3],[4]

0.82%

[3],[4]

0.80%

[3],[5]

0.84%

[1],[3],[5]

0.70%

[3],[6]

0.70%

[2],[3],[6]

Total expenses excluding management fees

0.19%

[3]

0.22%

[3]

4.07%

[3]

3.56%

[3]

4.54%

[3]

3.50%

[1],[3]

4.14%

[3]

3.56%

[2],[3]

Expenses waived

-0.65%

-3.87%

[3]

-3.38%

[3]

-0.80%

-4.28%

[3]

-3.22%

[1],[3]

-0.70%

-3.94%

[3]

-3.38%

[2],[3]

Net expenses excluding management fees

0.20%

[3]

0.18%

[3]

0.25%

[3]

0.28%

[1],[3]

0.20%

[3]

0.18%

[2],[3]

Net income (loss)

-4.16%

3.75%

-12.11%

7.75%

-7.82%

12.06%

[1]

-12.42%

9.96%

[2]

[1]

USAG commenced operations on April 13, 2012.

[2]

USMI commenced operations on June 19, 2012.

[3]

Annualized.

[4]

Effective as of May 29, 2012 (and continuing at least through May 1, 2014), USCF voluntarily agreed to waive the management fee paid by CPER from 0.95% to 0.65% per annum of average daily total net assets.

[5]

Effective as of May 29, 2012 (and continuing at least through May 1, 2014), USCF voluntarily agreed to waive the management fee paid by USAG from 0.95% to 0.80% per annum of average daily total net assets.

[6]

Effective as of May 30, 2012 (and continuing at least through May 1, 2014), USCF voluntarily agreed to waive the management fee paid by USMI from 0.95% to 0.70% per annum of average daily total net assets. The reduced fee became operational as of June 19, 2012.

Financial_Highlights_Per_Unit_1

Financial Highlights (Per Unit Performance Data and Other Supplemental Financial Data) (Parenthetical) (Details)

0 Months Ended

9 Months Ended

0 Months Ended

9 Months Ended

0 Months Ended

9 Months Ended

0 Months Ended

29-May-12

Sep. 30, 2013

Sep. 30, 2012

29-May-12

Sep. 30, 2013

Sep. 30, 2012

29-May-12

30-May-12

Sep. 30, 2013

Sep. 30, 2012

30-May-12

United States Copper Index Fund [Member]

United States Agriculture Index Fund [Member]

United States Metals Index Fund [Member]

Maximum [Member]

Minimum [Member]

Maximum [Member]

Minimum [Member]

Maximum [Member]

Minimum [Member]

Average Sales Price and Production Costs Per Unit of Production [Line Items]

Percentage of average daily net assets paid monthly, waiver expense

0.65%

3.87%

[1]

3.38%

[1]

0.95%

0.65%

0.80%

4.28%

[1]

3.22%

[1],[2]

0.95%

0.80%

0.70%

3.94%

[1]

3.38%

[1],[3]

0.95%

0.70%

[1]

Annualized.

[2]

USAG commenced operations on April 13, 2012.

[3]

USMI commenced operations on June 19, 2012.

Fair_Value_of_Financial_Instru2

Fair Value of Financial Instruments (Valuation of Securities Using Fair Value Hierarchy) (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
United States Commodity Index Fund [Member] \| Short-Term Investments [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	$345,168,420	$435,149,105
United States Commodity Index Fund [Member] \| Exchange-Traded Futures Contracts [Member] \| Foreign [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	-1,675,599	2,901,485
United States Commodity Index Fund [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	2,467,721	-8,122,385
United States Commodity Index Fund [Member] \| Fair Value, Inputs, Level 1 [Member] \| Short-Term Investments [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	345,168,420	435,149,105
United States Commodity Index Fund [Member] \| Fair Value, Inputs, Level 1 [Member] \| Exchange-Traded Futures Contracts [Member] \| Foreign [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	-1,675,599	2,901,485
United States Commodity Index Fund [Member] \| Fair Value, Inputs, Level 1 [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	2,467,721	-8,122,385
United States Copper Index Fund [Member] \| Short-Term Investments [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	1,299,865	2,149,689
United States Copper Index Fund [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	25,075	6,575
United States Copper Index Fund [Member] \| Fair Value, Inputs, Level 1 [Member] \| Short-Term Investments [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	1,299,865	2,149,689
United States Copper Index Fund [Member] \| Fair Value, Inputs, Level 1 [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	25,075	6,575
United States Agriculture Index Fund [Member] \| Short-Term Investments [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	1,249,883	2,199,688
United States Agriculture Index Fund [Member] \| Exchange-Traded Futures Contracts [Member] \| Foreign [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	26,546	-31,470
United States Agriculture Index Fund [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	-62,474	-87,685
United States Agriculture Index Fund [Member] \| Fair Value, Inputs, Level 1 [Member] \| Short-Term Investments [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	1,249,883	2,199,688
United States Agriculture Index Fund [Member] \| Fair Value, Inputs, Level 1 [Member] \| Exchange-Traded Futures Contracts [Member] \| Foreign [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	26,546	-31,470
United States Agriculture Index Fund [Member] \| Fair Value, Inputs, Level 1 [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	-62,474	-87,685
United States Metals Index Fund [Member] \| Short-Term Investments [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	1,549,823	2,349,792
United States Metals Index Fund [Member] \| Exchange-Traded Futures Contracts [Member] \| Foreign [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	-12,742	77,393
United States Metals Index Fund [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	-14,453	-31,335
United States Metals Index Fund [Member] \| Fair Value, Inputs, Level 1 [Member] \| Short-Term Investments [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	1,549,823	2,349,792
United States Metals Index Fund [Member] \| Fair Value, Inputs, Level 1 [Member] \| Exchange-Traded Futures Contracts [Member] \| Foreign [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	-12,742	77,393
United States Metals Index Fund [Member] \| Fair Value, Inputs, Level 1 [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Securities, fair value	($14,453)	($31,335)

Fair_Value_of_Financial_Instru3

Fair Value of Financial Instruments (Fair Value of Derivative Instrument held by Usci, Cper, Usag and Usmi) (Details) (Commodity Contracts [Member], Futures [Member], Assets [Member], USD $)	Sep. 30, 2013	Dec. 31, 2012
United States Commodity Index Fund [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not Accounted for as Hedging Instruments	$792,122	($5,220,900)
United States Copper Index Fund [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not Accounted for as Hedging Instruments	25,075	6,575
United States Agriculture Index Fund [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not Accounted for as Hedging Instruments	-35,928	-119,155
United States Metals Index Fund [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not Accounted for as Hedging Instruments	($27,195)	$46,058

Fair_Value_of_Financial_Instru4

Fair Value of Financial Instruments (Effect of Derivative Instruments on Statements of Operations of Usci, Cper, Usag and Usmi) (Details) (USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Realized gain (loss) on closed positions	($2,505,308)		$21,279,445		($23,861,351)		($11,794,178)
Change in Unrealized Gain or (Loss) on Derivatives Recognized in Income	'		'		6,041,496		31,489,301
United States Commodity Index Fund [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Realized gain (loss) on closed positions	-2,442,019		20,615,262		-23,085,330		-12,231,495
Change in Unrealized Gain or (Loss) on Derivatives Recognized in Income	'		'		6,013,022		31,016,267
United States Commodity Index Fund [Member] \| Commodity Contracts [Member] \| Futures [Member] \| Realized gain (loss) on closed positions [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Realized gain (loss) on closed positions	'		'		-23,085,330		-12,231,495
United States Commodity Index Fund [Member] \| Commodity Contracts [Member] \| Futures [Member] \| Change in unrealized gain (loss) on open positions [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Change in Unrealized Gain or (Loss) on Derivatives Recognized in Income	'		'		6,013,022		31,016,267
United States Copper Index Fund [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Realized gain (loss) on closed positions	-60,425		19,112		-285,950		-63,313
Change in Unrealized Gain or (Loss) on Derivatives Recognized in Income	'		'		18,500		278,838
United States Copper Index Fund [Member] \| Commodity Contracts [Member] \| Futures [Member] \| Realized gain (loss) on closed positions [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Realized gain (loss) on closed positions	'		'		-285,950		-63,313
United States Copper Index Fund [Member] \| Commodity Contracts [Member] \| Futures [Member] \| Change in unrealized gain (loss) on open positions [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Change in Unrealized Gain or (Loss) on Derivatives Recognized in Income	'		'		18,500		278,838
United States Agriculture Index Fund [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Realized gain (loss) on closed positions	12,807	[1]	482,644	[1]	-253,247	[1]	368,209	[1]
Change in Unrealized Gain or (Loss) on Derivatives Recognized in Income	'		'		83,227		18,483
United States Agriculture Index Fund [Member] \| Commodity Contracts [Member] \| Futures [Member] \| Realized gain (loss) on closed positions [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Realized gain (loss) on closed positions	'		'		-253,247		368,209	[2]
United States Agriculture Index Fund [Member] \| Commodity Contracts [Member] \| Futures [Member] \| Change in unrealized gain (loss) on open positions [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Change in Unrealized Gain or (Loss) on Derivatives Recognized in Income	'		'		83,227		18,483	[2]
United States Metals Index Fund [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Realized gain (loss) on closed positions	-15,671	[3]	162,427	[3]	-236,824	[3]	132,421	[3]
United States Metals Index Fund [Member] \| Commodity Contracts [Member] \| Futures [Member] \| Realized gain (loss) on closed positions [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Realized gain (loss) on closed positions	'		'		-236,824		132,421	[4]
United States Metals Index Fund [Member] \| Commodity Contracts [Member] \| Futures [Member] \| Change in unrealized gain (loss) on open positions [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Change in Unrealized Gain or (Loss) on Derivatives Recognized in Income	'		'		($73,253)		$175,713	[4]

[1]	The commencement of operations of the United States Agriculture Index Fund was April 13, 2012.
[2]	USAG commenced operations on April 13, 2012.
[3]	The commencement of operations of the United States Metals Index Fund was June 19, 2012.
[4]	USMI commenced operations on June 19, 2012.