United States Copper Index Fund (CPER) 10-Q7 May 152015 Q1 Quarterly reportFinancial data

Company Profile

Document_And_Entity_Informatio

Document And Entity Information	3 Months Ended
Document And Entity Information	Mar. 31, 2015
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Trading Symbol	USCI
Entity Common Stock, Shares Outstanding	0
Entity Registrant Name	United States Commodity Index Funds Trust
Entity Central Index Key	1479247
Current Fiscal Year End Date	-19
Entity Filer Category	Accelerated Filer

Condensed_Statements_of_Financ

Condensed Statements of Financial Condition (USD $)	Mar. 31, 2015		Dec. 31, 2014
Assets
Cash and cash equivalents (Notes 2 and 6)	$487,872,320		$718,659,173
Equity in trading accounts:
Cash and cash equivalents	68,931,719		81,100,456
Unrealized gain (loss) on open commodity futures contracts	-35,346,478		-38,667,824
Receivable from Sponsor (Note 4)	20,723		119,754
Interest receivable	1,333		1,343
Directors' fees and insurance receivable	55,831		0
ETF transaction fees receivable	0		1,050
Total assets	521,535,448		761,213,952
Liabilities and Capital
Payable for shares redeemed	0		43,736,649
Management fees payable (Note 4)	431,525		535,815
Professional fees payable	349,643		618,128
Brokerage commissions payable	42,815		42,815
Directors' fees and insurance payable	0		15,856
Total liabilities	823,983		44,949,263
Commitments and Contingencies (Notes 4, 5 and 6)
Capital
Sponsor	0		0
Shareholders	520,711,465		716,264,689
Total Capital	520,711,465		716,264,689
Total liabilities and capital	521,535,448		761,213,952
Shares outstanding	11,700,000		15,050,000
United States Commodity Index Fund [Member]
Assets
Cash and cash equivalents (Notes 2 and 6)	484,223,716		711,984,950
Equity in trading accounts:
Cash and cash equivalents	68,568,239		80,222,326
Unrealized gain (loss) on open commodity futures contracts	-35,294,492		-38,267,159
Interest receivable	1,261		1,261
Directors' fees and insurance receivable	55,511		0
ETF transaction fees receivable	0		1,050
Total assets	517,554,235		753,942,428
Liabilities and Capital
Payable for shares redeemed	0		43,736,649
Management fees payable (Note 4)	429,349		531,781
Professional fees payable	311,877		494,705
Brokerage commissions payable	42,815		42,815
Directors' fees and insurance payable	0		15,638
Total liabilities	784,041		44,821,588
Commitments and Contingencies (Notes 4, 5 and 6)
Capital
Sponsor	0		0
Shareholders	516,770,194		709,120,840
Total Capital	516,770,194		709,120,840
Total liabilities and capital	517,554,235		753,942,428
Shares outstanding	11,500,000		14,700,000
Net asset value per share	$44.94		$48.24
Market value per share	$44.92		$48.29
United States Copper Index Fund [Member]
Assets
Cash and cash equivalents (Notes 2 and 6)	1,666,839		2,729,373
Equity in trading accounts:
Cash and cash equivalents	147,514		337,148
Unrealized gain (loss) on open commodity futures contracts	49,713		-197,525
Receivable from Sponsor (Note 4)	10,825		42,830
Interest receivable	26		25
Directors' fees and insurance receivable	233		0
Total assets	1,875,150		2,911,851
Liabilities and Capital
Management fees payable (Note 4)	1,007		1,612
Professional fees payable	20,642		44,577
Directors' fees and insurance payable	0		35
Total liabilities	21,649		46,224
Commitments and Contingencies (Notes 4, 5 and 6)
Capital
Sponsor	0		0
Shareholders	1,853,501		2,865,627
Total Capital	1,853,501		2,865,627
Total liabilities and capital	1,875,150		2,911,851
Shares outstanding	100,000		150,000
Net asset value per share	$18.54		$19.10
Market value per share	$18.59		$19.02
United States Agriculture Index Fund [Member]
Assets
Cash and cash equivalents (Notes 2 and 6)	1,981,765		2,142,415
Equity in trading accounts:
Cash and cash equivalents	215,966		222,826
Unrealized gain (loss) on open commodity futures contracts	-101,699		-66,576
Receivable from Sponsor (Note 4)	9,898		39,139
Interest receivable	46		46
Directors' fees and insurance receivable	87		0
Total assets	2,106,063		2,337,850
Liabilities and Capital
Management fees payable (Note 4)	1,169		1,294
Professional fees payable	17,124		39,850
Directors' fees and insurance payable	0		104
Total liabilities	18,293		41,248
Commitments and Contingencies (Notes 4, 5 and 6)
Capital
Sponsor	0		0
Shareholders	2,087,770		2,296,602
Total Capital	2,087,770		2,296,602
Total liabilities and capital	2,106,063		2,337,850
Shares outstanding	100,000		100,000
Net asset value per share	$20.88		$22.97
Market value per share	$20.27		$22.57
United States Metals Index Fund [Member]
Assets
Cash and cash equivalents (Notes 2 and 6)	0	[1]	1,802,435
Equity in trading accounts:
Cash and cash equivalents	0	[1]	318,156
Unrealized gain (loss) on open commodity futures contracts	0	[1]	-136,564
Receivable from Sponsor (Note 4)	0		37,785
Interest receivable	0	[1]	11
Total assets	0	[1]	2,021,823
Liabilities and Capital
Management fees payable (Note 4)	0	[1]	1,128
Professional fees payable	0	[1]	38,996
Directors' fees and insurance payable	0	[1]	79
Total liabilities	0	[1]	40,203
Commitments and Contingencies (Notes 4, 5 and 6)		[1]
Capital
Sponsor	0	[1]	0
Shareholders	0	[1]	1,981,620
Total Capital	0	[1]	1,981,620
Total liabilities and capital	$0	[1]	$2,021,823
Shares outstanding	0	[1]	100,000
Net asset value per share	$0	[1]	$19.82	[1]
Market value per share	$0	[1]	$19.55

[1]	USMI ceased trading on the NYSE Arca on March 18, 2015 and the Fund's liquidation date was March 24, 2015.

Condensed_Schedule_of_Investme

Condensed Schedule of Investments (USD $)	Mar. 31, 2015
Condensed Schedule of Investments (USD $)	Conntract
United States Commodity Index Fund [Member]
Number of Contracts	14,595	[1]
Unrealized Gain (Loss) on Open Commodity Contracts	($35,294,492)	[1]
% of Capital	-6.83%	[1]
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member]
Number of Contracts	6,866
Unrealized Gain (Loss) on Open Commodity Contracts	-35,631,576
% of Capital	-6.89%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Aluminum Futures LA September 2015 contracts, expiring September 2015 [Member]
Number of Contracts	1,351
Unrealized Gain (Loss) on Open Commodity Contracts	-10,130,119
% of Capital	-1.96%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Zinc Futures LX April 2015 contracts, expiring April 2015 [Member]
Number of Contracts	1,183
Unrealized Gain (Loss) on Open Commodity Contracts	-7,981,362
% of Capital	-1.54%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Nickel Futures LN June 2015 contracts, expiring June 2015 [Member]
Number of Contracts	692
Unrealized Gain (Loss) on Open Commodity Contracts	-16,160,976
% of Capital	-3.13%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Lead Futures LL June 2015 contracts, expiring June 2015 [Member]
Number of Contracts	822
Unrealized Gain (Loss) on Open Commodity Contracts	-228,004
% of Capital	-0.04%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Gasoil Futures QS May 2015 contracts, expiring May 2015 [Member]
Number of Contracts	701
Unrealized Gain (Loss) on Open Commodity Contracts	-597,525
% of Capital	-0.12%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Zinc Futures LX May 2015 contracts, expiring May 2015 [Member]
Number of Contracts	730
Unrealized Gain (Loss) on Open Commodity Contracts	-171,800
% of Capital	-0.03%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Cocoa Futures CC December 2015 contracts, expiring December 2015 [Member]
Number of Contracts	1,387
Unrealized Gain (Loss) on Open Commodity Contracts	-361,790
% of Capital	-0.07%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member]
Number of Contracts	5,809
Unrealized Gain (Loss) on Open Commodity Contracts	-3,341,048
% of Capital	-0.65%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Corn Futures C December 2015 contracts, expiring December 2015 [Member]
Number of Contracts	1,837
Unrealized Gain (Loss) on Open Commodity Contracts	-1,179,187
% of Capital	-0.23%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| COMEX Copper Futures HG July 2015 contracts, expiring July 2015 [Member]
Number of Contracts	542
Unrealized Gain (Loss) on Open Commodity Contracts	-488,988
% of Capital	-0.10%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| COMEX Silver Futures SI July 2015 contracts, expiring July 2015 [Member]
Number of Contracts	443
Unrealized Gain (Loss) on Open Commodity Contracts	-582,815
% of Capital	-0.11%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Feeder Cattle Futures FC May 2015 contracts, expiring May 2015 [Member]
Number of Contracts	353	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	-15,888	[2]
% of Capital	0.00%	[2]
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Live Cattle Futures LC June 2015 contracts, expiring June 2015 [Member]
Number of Contracts	626
Unrealized Gain (Loss) on Open Commodity Contracts	-38,190
% of Capital	-0.01%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| NYMEX Heating Oil Futures HO June 2015 contracts, expiring May 2015 [Member]
Number of Contracts	506
Unrealized Gain (Loss) on Open Commodity Contracts	-582,880
% of Capital	-0.11%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Soybean Meal Futures SM July 2015 contracts, expiring July 2015 [Member]
Number of Contracts	1,187
Unrealized Gain (Loss) on Open Commodity Contracts	359,030
% of Capital	0.07%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| COMEX Gold Futures GC December 2015 contracts, expiring December 2015 [Member]
Number of Contracts	315
Unrealized Gain (Loss) on Open Commodity Contracts	-812,130
% of Capital	-0.16%
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member]
Number of Contracts	1,920	[3]
Unrealized Gain (Loss) on Open Commodity Contracts	3,678,132	[3]
% of Capital	0.71%	[3]
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Aluminum Futures LA September 2015 contracts, expiring September 2015 [Member]
Number of Contracts	509	[3]
Unrealized Gain (Loss) on Open Commodity Contracts	701,061	[3]
% of Capital	0.13%	[3]
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Zinc Futures LX April 2015 contracts, expiring April 2015 [Member]
Number of Contracts	1,183	[3]
Unrealized Gain (Loss) on Open Commodity Contracts	342,900	[3]
% of Capital	0.07%	[3]
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Nickel Futures LN June 2015 contracts, expiring June 2015 [Member]
Number of Contracts	228	[3]
Unrealized Gain (Loss) on Open Commodity Contracts	2,634,171	[3]
% of Capital	0.51%	[3]
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member]
Market Value	369,909,971
% of Capital	71.58%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 4/30/2015 [Member]
Principal Amount	40,000,000
Market Value	39,998,228
% of Capital	7.74%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 5/14/2015 [Member]
Principal Amount	40,000,000
Market Value	39,997,133
% of Capital	7.74%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.07%, 5/21/2015 [Member]
Principal Amount	40,000,000
Market Value	39,996,389
% of Capital	7.74%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.07%, 5/28/2015 [Member]
Principal Amount	40,000,000
Market Value	39,995,567
% of Capital	7.74%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.08%, 6/04/2015 [Member]
Principal Amount	30,000,000
Market Value	29,996,000
% of Capital	5.81%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.11%, 6/18/2015 [Member]
Principal Amount	30,000,000
Market Value	29,993,175
% of Capital	5.80%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.15%, 9/17/2015 [Member]
Principal Amount	40,000,000
Market Value	39,971,833
% of Capital	7.73%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| Group Thirty Nine [Member]
Principal Amount	30,000,000
Market Value	29,993,385
% of Capital	5.80%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| Group Fourty [Member]
Principal Amount	40,000,000
Market Value	39,985,361
% of Capital	7.74%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| Group Fourty One [Member]
Principal Amount	40,000,000
Market Value	39,982,900
% of Capital	7.74%
United States Copper Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| COMEX Copper Futures HG May 2015 Contracts, expiring May 2015 [Member]
Number of Contracts	27	[4]
Unrealized Gain (Loss) on Open Commodity Contracts	49,713	[4]
% of Capital	2.68%	[4]
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member]
Market Value	1,399,814
% of Capital	75.52%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 5/14/2015 [Member]
Principal Amount	500,000
Market Value	499,964
% of Capital	26.97%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.07%, 5/21/2015 [Member]
Principal Amount	400,000
Market Value	399,964
% of Capital	21.58%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.11%, 6/18/2015 [Member]
Principal Amount	500,000
Market Value	499,886
% of Capital	26.97%
United States Agriculture Index Fund [Member]
Number of Contracts	82	[5]
Unrealized Gain (Loss) on Open Commodity Contracts	-101,699	[5]
% of Capital	-4.87%	[5]
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member]
Number of Contracts	41
Unrealized Gain (Loss) on Open Commodity Contracts	-93,477
% of Capital	-4.48%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Coffee-C Futures KC July 2015 contracts, expiring July 2015 [Member]
Number of Contracts	4
Unrealized Gain (Loss) on Open Commodity Contracts	-93,656
% of Capital	-4.48%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Sugar 11 Futures SB July 2015 contracts, expiring June 2015 [Member]
Number of Contracts	13
Unrealized Gain (Loss) on Open Commodity Contracts	-2,688
% of Capital	-0.13%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-Canola Futures RS July 2015 contracts, expiring July 2015 [Member]
Number of Contracts	15
Unrealized Gain (Loss) on Open Commodity Contracts	232
% of Capital	0.01%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Cotton 2 Futures CT July 2015 contracts, expiring July 2015 [Member]
Number of Contracts	3
Unrealized Gain (Loss) on Open Commodity Contracts	4,435
% of Capital	0.21%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Cocoa Futures CC December 2015 contracts, expiring December 2015 [Member]
Number of Contracts	6
Unrealized Gain (Loss) on Open Commodity Contracts	-1,800
% of Capital	-0.09%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member]
Number of Contracts	41
Unrealized Gain (Loss) on Open Commodity Contracts	-8,222
% of Capital	-0.39%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Wheat Futures W July 2015 contracts, expiring July 2015 [Member]
Number of Contracts	5
Unrealized Gain (Loss) on Open Commodity Contracts	-1,300
% of Capital	-0.06%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Soybean Oil Futures BO July 2015 contracts, expiring July 2015 [Member]
Number of Contracts	1
Unrealized Gain (Loss) on Open Commodity Contracts	-2,670
% of Capital	-0.13%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Corn Futures C December 2015 contracts, expiring December 2015 [Member]
Number of Contracts	15
Unrealized Gain (Loss) on Open Commodity Contracts	-9,587
% of Capital	-0.45%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Feeder Cattle Futures FC May 2015 contracts, expiring May 2015 [Member]
Number of Contracts	1
Unrealized Gain (Loss) on Open Commodity Contracts	-150
% of Capital	-0.01%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Live Cattle Futures LC June 2015 contracts, expiring June 2015 [Member]
Number of Contracts	4	[2]
Unrealized Gain (Loss) on Open Commodity Contracts	50	[2]
% of Capital	0.00%	[2]
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| KCBT Hard Red Winter Wheat Futures KW July 2015 contracts, expiring July 2015 [Member]
Number of Contracts	2
Unrealized Gain (Loss) on Open Commodity Contracts	-813
% of Capital	-0.04%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Lean Hogs Futures LH August 2015 contracts, expiring August 2015 [Member]
Number of Contracts	3
Unrealized Gain (Loss) on Open Commodity Contracts	620
% of Capital	0.03%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Soybean Meal Futures SM October 2015 contracts, expiring October 2015 [Member]
Number of Contracts	5
Unrealized Gain (Loss) on Open Commodity Contracts	1,840
% of Capital	0.09%
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Soybean Futures S November 2015 contracts, expiring November 2015 [Member]
Number of Contracts	5
Unrealized Gain (Loss) on Open Commodity Contracts	3,788
% of Capital	0.18%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member]
Market Value	1,599,744
% of Capital	76.62%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 4/23/2015 [Member]
Principal Amount	100,000
Market Value	99,997
% of Capital	4.79%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 4/30/2015 [Member]
Principal Amount	200,000
Market Value	199,991
% of Capital	9.58%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 5/14/2015 [Member]
Principal Amount	200,000
Market Value	199,986
% of Capital	9.58%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.07%, 5/21/2015 [Member]
Principal Amount	500,000
Market Value	499,955
% of Capital	23.95%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.11%, 6/18/2015 [Member]
Principal Amount	500,000
Market Value	499,886
% of Capital	23.94%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.15%, 9/17/2015 [Member]
Principal Amount	100,000
Market Value	$99,929
% of Capital	4.78%

[1]	Collateral amounted to $68,568,239 on open futures contracts.
[2]	Represents less than 0.005%.
[3]	All short contracts are offset by the same number of Futures Contracts in the corresponding long positions and are acquired solely for the purpose of reducing a long position (e.g., due to a redemption or to reflect a rebalancing of the SDCI).
[4]	Collateral amounted to $147,514 on open futures contracts.
[5]	Collateral amounted to $215,966 on open futures contracts.

Condensed_Schedule_of_Investme1

Condensed Schedule of Investments (Parenthetical) (USD $)	3 Months Ended
Condensed Schedule of Investments (Parenthetical) (USD $)	Mar. 31, 2015
United States Commodity Index Fund [Member]
Debt Instrument, Collateral Amount	68,568,239
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Aluminum Futures LA September 2015 contracts, expiring September 2015 [Member]
Expiration date	Sep-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| Lme Zinc Futures Lx April 2015 Contracts Expiring April 2015 [Member]
Expiration date	Apr-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Nickel Futures LN June 2015 contracts, expiring June 2015 [Member]
Expiration date	Jun-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Lead Futures LL June 2015 contracts, expiring June 2015 [Member]
Expiration date	Jun-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Gasoil Futures QS May 2015 contracts, expiring May 2015 [Member]
Expiration date	May-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| LME Zinc Futures LX May 2015 contracts, expiring May 2015 [Member]
Expiration date	May-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Cocoa Futures CC December 2015 contracts, expiring December 2015 [Member]
Expiration date	Dec-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| CBOT Soybean Meal Futures SM July 2015 contracts, expiring July 2015 [Member]
Expiration date	Jul-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States [Member] \| COMEX Gold Futures GC December 2015 contracts, expiring December 2015 [Member]
Expiration date	Dec-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Corn Futures C December 2015 contracts, expiring December 2015 [Member]
Expiration date	Dec-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| COMEX Copper Futures HG July 2015 contracts, expiring July 2015 [Member]
Expiration date	Jul-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| ICE-US Cocoa Futures CC December 2015 contracts, expiring December 2015 [Member]
Expiration date	Dec-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Feeder Cattle Futures FC May 2015 contracts, expiring May 2015 [Member]
Expiration date	May-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Live Cattle Futures LC June 2015 contracts, expiring June 2015 [Member]
Expiration date	Jun-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| COMEX Silver Futures SI July 2015 contracts, expiring July 2015 [Member]
Expiration date	Jul-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| NYMEX Heating Oil Futures HO June 2015 contracts, expiring May 2015 [Member]
Expiration date	May-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Zinc Futures LX April 2015 contracts, expiring April 2015 [Member]
Expiration date	Apr-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Aluminum Futures LA September 2015 contracts, expiring September 2015 [Member]
Expiration date	Sep-15
United States Commodity Index Fund [Member] \| Open Futures Contracts, Short [Member] \| Foreign [Member] \| LME Nickel Futures LN June 2015 contracts, expiring June 2015 [Member]
Expiration date	Jun-15
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 4/30/2015 [Member]
Expiration date	4/30/15
Interest rate	0.06%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 5/14/2015 [Member]
Expiration date	5/14/15
Interest rate	0.06%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.07%, 5/21/2015 [Member]
Expiration date	5/21/15
Interest rate	0.07%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.07%, 5/28/2015 [Member]
Expiration date	5/28/15
Interest rate	0.07%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.08%, 6/04/2015 [Member]
Expiration date	6/4/15
Interest rate	0.08%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.11%, 6/18/2015 [Member]
Expiration date	6/18/15
Interest rate	0.11%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.15%, 9/17/2015 [Member]
Expiration date	9/17/15
Interest rate	0.15%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 8/06/2015 [Member]
Expiration date	8/6/15
Interest rate	0.06%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.09%, 9/03/2015 [Member]
Expiration date	9/3/15
Interest rate	0.09%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.10%, 9/10/2015 [Member]
Expiration date	9/10/15
Interest rate	0.10%
United States Copper Index Fund [Member]
Debt Instrument, Collateral Amount	147,514
United States Copper Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| COMEX Copper Futures HG May 2015 Contracts, expiring May 2015 [Member]
Expiration date	May-15
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 5/14/2015 [Member]
Expiration date	5/14/15
Interest rate	0.06%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.07%, 5/21/2015 [Member]
Expiration date	5/21/15
Interest rate	0.07%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.11%, 6/18/2015 [Member]
Expiration date	6/18/15
Interest rate	0.11%
United States Agriculture Index Fund [Member]
Debt Instrument, Collateral Amount	215,966
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Coffee-C Futures KC July 2015 contracts, expiring July 2015 [Member]
Expiration date	Jul-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Sugar 11 Futures SB July 2015 contracts, expiring June 2015 [Member]
Expiration date	Jun-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-Canola Futures RS July 2015 contracts, expiring July 2015 [Member]
Expiration date	Jul-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Cotton 2 Futures CT July 2015 contracts, expiring July 2015 [Member]
Expiration date	Jul-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| Foreign [Member] \| ICE-US Cocoa Futures CC December 2015 contracts, expiring December 2015 [Member]
Expiration date	Dec-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Wheat Futures W July 2015 contracts, expiring July 2015 [Member]
Expiration date	Jul-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Soybean Oil Futures BO July 2015 contracts, expiring July 2015 [Member]
Expiration date	Jul-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Corn Futures C December 2015 contracts, expiring December 2015 [Member]
Expiration date	Dec-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Feeder Cattle Futures FC May 2015 contracts, expiring May 2015 [Member]
Expiration date	May-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Live Cattle Futures LC June 2015 contracts, expiring June 2015 [Member]
Expiration date	Jun-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| KCBT Hard Red Winter Wheat Futures KW July 2015 contracts, expiring July 2015 [Member]
Expiration date	Jul-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CME Lean Hogs Futures LH August 2015 contracts, expiring August 2015 [Member]
Expiration date	Aug-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Soybean Meal Futures SM October 2015 contracts, expiring October 2015 [Member]
Expiration date	Oct-15
United States Agriculture Index Fund [Member] \| Open Futures Contracts, Long [Member] \| United States Contracts [Member] \| CBOT Soybean Futures S November 2015 contracts, expiring November 2015 [Member]
Expiration date	Nov-15
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.05%, 4/23/2015 [Member]
Expiration date	4/23/15
Interest rate	0.05%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 4/30/2015 [Member]
Expiration date	4/30/15
Interest rate	0.06%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.06%, 5/14/2015 [Member]
Expiration date	5/14/15
Interest rate	0.06%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.07%, 5/21/2015 [Member]
Expiration date	5/21/15
Interest rate	0.07%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.11%, 6/18/2015 [Member]
Expiration date	6/18/15
Interest rate	0.11%
United States Agriculture Index Fund [Member] \| Cash Equivalents [Member] \| US Treasury Securities [Member] \| U.S.Treasury Bills 0.15%, 9/17/2015 [Member]
Expiration date	9/17/15
Interest rate	0.15%

Condensed_Statements_of_Operat

Condensed Statements of Operations (USD $)	3 Months Ended
Condensed Statements of Operations (USD $)	Mar. 31, 2015		Mar. 31, 2014
Gain (loss) on trading of commodity futures contracts:
Realized gain (loss) on closed positions	($49,673,132)		$27,005,397
Change in unrealized gain (loss) on open positions	3,321,346		-1,495,984
Realized gain (loss) on foreign currency transactions	53		-118
Realized gain (loss) on short-term investments	3,812		0
Change in unrealized gain (loss) on foreign currency translations	-32		-3
Interest income	81,858		71,524
ETF transaction fees	4,900		3,500
Total income (loss)	-46,261,195		25,584,316
Expenses
Management fees (Note 4)	1,319,960		1,272,305
Professional fees	291,772		154,260
Brokerage commissions	200,410		102,209
Directors' fees and insurance	27,884		31,130
Total expenses	1,840,026		1,559,904
Expense waiver (Note 4)	-29,608		-23,362
Net expenses	1,810,418		1,536,542
Net income (loss)	-48,071,613		24,047,774
United States Commodity Index Fund Trust [Member]
Gain (loss) on trading of commodity futures contracts:
Realized gain (loss) on closed positions	-48,958,657		26,871,173
Change in unrealized gain (loss) on open positions	2,972,667		-1,482,624
Realized gain (loss) on foreign currency transactions	0		4
Realized gain (loss) on short-term investments	3,645		0
Change in unrealized gain (loss) on foreign currency translations	0		-3
Interest income	81,071		70,654
ETF transaction fees	4,200		3,150
Total income (loss)	-45,897,074		25,462,354
Expenses
Management fees (Note 4)	1,311,264		1,260,019
Professional fees	261,536		128,340
Brokerage commissions	199,183		101,246
Directors' fees and insurance	27,613		30,717
Total expenses	1,799,596		1,520,322
Net income (loss)	-47,696,670		23,942,032
Net income (loss) per share	($3.30)		$2.54
Net income (loss) per weighted average share	($3.34)		$2.54
Weighted average shares outstanding	14,291,111		9,419,444
United States Copper Index Fund [Member]
Gain (loss) on trading of commodity futures contracts:
Realized gain (loss) on closed positions	-362,375		5,663
Change in unrealized gain (loss) on open positions	247,238		-225,900
Realized gain (loss) on short-term investments	17		0
Interest income	301		306
ETF transaction fees	350		350
Total income (loss)	-114,469		-219,581
Expenses
Management fees (Note 4)	3,103		3,692
Professional fees	11,185		15,120
Brokerage commissions	260		368
Directors' fees and insurance	99		136
Total expenses	14,647		19,316
Expense waiver (Note 4)	-10,824		-14,268
Net expenses	3,823		5,048
Net income (loss)	-118,292		-224,629
Net income (loss) per share	($0.56)		($2.49)
Net income (loss) per weighted average share	($1.10)		($2.09)
Weighted average shares outstanding	107,778		107,222
United States Agricultural Index Fund [Member]
Gain (loss) on trading of commodity futures contracts:
Realized gain (loss) on closed positions	-169,684		160,134
Change in unrealized gain (loss) on open positions	-35,123		190,023
Realized gain (loss) on foreign currency transactions	53		-122
Change in unrealized gain (loss) on foreign currency translations	-32		0
Interest income	328		308
Total income (loss)	-204,458		350,343
Expenses
Management fees (Note 4)	3,498		4,781
Professional fees	10,008		5,400
Brokerage commissions	658		401
Directors' fees and insurance	101		141
Total expenses	14,265		10,723
Expense waiver (Note 4)	-9,891		-4,511
Net expenses	4,374		6,212
Net income (loss)	-208,832		344,131
Net income (loss) per share	($2.09)		$3.44
Net income (loss) per weighted average share	($2.09)		$3.44
Weighted average shares outstanding	100,000		100,000
United States Metals Index Fund [Member]
Gain (loss) on trading of commodity futures contracts:
Realized gain (loss) on closed positions	-182,416	[1]	-31,573
Change in unrealized gain (loss) on open positions	136,564	[1]	22,517
Realized gain (loss) on short-term investments	150	[1]	0
Interest income	158	[1]	256
ETF transaction fees	350	[1]	0
Total income (loss)	-45,194	[1]	-8,800
Expenses
Management fees (Note 4)	2,095	[1]	3,813
Professional fees	9,043	[1]	5,400
Brokerage commissions	309	[1]	194
Directors' fees and insurance	71	[1]	136
Total expenses	11,518	[1]	9,543
Expense waiver (Note 4)	-8,893	[1]	-4,583
Net expenses	2,625	[1]	4,960
Net income (loss)	($47,819)	[1]	($13,760)
Net income (loss) per share	($19.82)	[1]	($0.14)
Net income (loss) per weighted average share	($0.72)	[1]	($0.14)
Weighted average shares outstanding	66,667	[1]	100,000

[1]	USMI ceased trading on the NYSE Arca on March 18, 2015 and the Fund's liquidation date was March 24, 2015.

Condensed_Statement_of_Changes

Condensed Statement of Changes in Capital (USD $)	3 Months Ended
Condensed Statement of Changes in Capital (USD $)	Mar. 31, 2015
Balances	$716,264,689
Net income (loss)	-48,071,613
Balances	520,711,465
United States Commodity Index Fund [Member]
Balances	709,120,840
Additions	39,544,842
Redemptions	-184,198,818
Net income (loss)	-47,696,670
Balances	516,770,194
Shares Outstanding	14,700,000
Additions	850,000
Redemptions	-4,050,000
Shares Outstanding	11,500,000
Net Asset Value Per Share:
Net asset value, beginning of period	$48.24
Net asset value, end of period	$44.94
United States Copper Index Fund [Member]
Balances	2,865,627
Additions	0
Redemptions	-893,834
Net income (loss)	-118,292
Balances	1,853,501
Shares Outstanding	150,000
Additions	0
Redemptions	-50,000
Shares Outstanding	100,000
Net Asset Value Per Share:
Net asset value, beginning of period	$19.10
Net asset value, end of period	$18.54
United States Agriculture Index Fund [Member]
Balances	2,296,602
Additions	0
Redemptions	0
Net income (loss)	-208,832
Balances	2,087,770
Shares Outstanding	100,000
Additions	0
Redemptions	0
Shares Outstanding	100,000
Net Asset Value Per Share:
Net asset value, beginning of period	$22.97
Net asset value, end of period	$20.88
United States Metals Index Fund [Member]
Balances	1,981,620
Additions	0	[1]
Redemptions	-1,933,801	[1]
Net income (loss)	-47,819	[1]
Balances	0	[1]
Shares Outstanding	100,000	[1]
Additions	0	[1]
Redemptions	-100,000	[1]
Shares Outstanding	0	[1]
Net Asset Value Per Share:
Net asset value, beginning of period	$19.82	[1]
Net asset value, end of period	$0	[1]
United States Commodity Index Funds Trust [Member]
Balances	716,264,689
Additions	39,544,842
Redemptions	-187,026,453
Net income (loss)	-48,071,613
Balances	520,711,465
Shares Outstanding	15,050,000
Additions	850,000
Redemptions	-4,200,000
Shares Outstanding	11,700,000
Sponsor [Member] \| United States Commodity Index Fund [Member]
Balances	0
Additions	0
Redemptions	0
Net income (loss)	0
Balances	0
Shares Outstanding	0
Additions	0
Redemptions	0
Shares Outstanding	0
Sponsor [Member] \| United States Copper Index Fund [Member]
Balances	0
Additions	0
Redemptions	0
Net income (loss)	0
Balances	0
Shares Outstanding	0
Additions	0
Redemptions	0
Shares Outstanding	0
Sponsor [Member] \| United States Agriculture Index Fund [Member]
Balances	0
Additions	0
Redemptions	0
Net income (loss)	0
Balances	0
Shares Outstanding	0
Additions	0
Redemptions	0
Shares Outstanding	0
Sponsor [Member] \| United States Metals Index Fund [Member]
Balances	0
Additions	0	[1]
Redemptions	0	[1]
Net income (loss)	0	[1]
Balances	0	[1]
Shares Outstanding	0	[1]
Additions	0	[1]
Redemptions	0	[1]
Shares Outstanding	0	[1]
Sponsor [Member] \| United States Commodity Index Funds Trust [Member]
Balances	0
Additions	0
Redemptions	0
Net income (loss)	0
Balances	0
Shares Outstanding	0
Additions	0
Redemptions	0
Shares Outstanding	0
Shareholders [Member] \| United States Commodity Index Fund [Member]
Balances	709,120,840
Additions	39,544,842
Redemptions	-184,198,818
Net income (loss)	-47,696,670
Balances	516,770,194
Shares Outstanding	14,700,000
Additions	850,000
Redemptions	-4,050,000
Shares Outstanding	11,500,000
Shareholders [Member] \| United States Copper Index Fund [Member]
Balances	2,865,627
Additions	0
Redemptions	-893,834
Net income (loss)	-118,292
Balances	1,853,501
Shares Outstanding	150,000
Additions	0
Redemptions	-50,000
Shares Outstanding	100,000
Shareholders [Member] \| United States Agriculture Index Fund [Member]
Balances	2,296,602
Additions	0
Redemptions	0
Net income (loss)	-208,832
Balances	2,087,770
Shares Outstanding	100,000
Additions	0
Redemptions	0
Shares Outstanding	100,000
Shareholders [Member] \| United States Metals Index Fund [Member]
Balances	1,981,620
Additions	0	[1]
Redemptions	-1,933,801	[1]
Net income (loss)	-47,819	[1]
Balances	0	[1]
Shares Outstanding	100,000	[1]
Additions	0	[1]
Redemptions	-100,000	[1]
Shares Outstanding	0	[1]
Shareholders [Member] \| United States Commodity Index Funds Trust [Member]
Balances	716,264,689
Additions	39,544,842
Redemptions	-187,026,453
Net income (loss)	-48,071,613
Balances	$520,711,465
Shares Outstanding	15,050,000
Additions	850,000
Redemptions	-4,200,000
Shares Outstanding	11,700,000

[1]	USMI ceased trading on the NYSE Arca on March 18, 2015 and the Fund's liquidation date was March 24, 2015.

Condensed_Statements_of_Cash_F

Condensed Statements of Cash Flows (USD $)	3 Months Ended
Condensed Statements of Cash Flows (USD $)	Mar. 31, 2015		Mar. 31, 2014
Cash Flows from Operating Activities:
Net income (loss)	($48,071,613)		$24,047,774
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Increase) decrease in commodity futures trading account - cash and cash equivalents	12,168,737		-22,998,822
Unrealized (gain) loss on open futures contracts	-3,321,346		1,495,984
(Increase) decrease in receivable from Sponsor	99,031		222,364
(Increase) decrease in interest receivable	10		0
(Increase) decrease in directors' fees and insurance receivable	-55,831		-27,018
(Increase) decrease in ETF transaction fees receivable	1,050		350
Increase (decrease) in management fees payable	-104,290		49,905
Increase (decrease) in professional fees payable	-268,485		-371,624
Increase (decrease) in directors' fees and insurance payable	-15,856		-8,303
Net cash provided by (used in) operating activities	-39,568,593		2,410,610
Cash Flows from Financing Activities:
Addition of shares	39,544,842		43,927,205
Redemption of shares	-230,763,102		0
Net cash provided by (used in) financing activities	-191,218,260		43,927,205
Net Increase (Decrease) in Cash and Cash Equivalents	-230,786,853		46,337,815
Cash and Cash Equivalents, beginning of year	718,659,173		480,181,509
Cash and Cash Equivalents, end of year	487,872,320		526,519,324
United States Commodity Index Fund [Member]
Cash Flows from Operating Activities:
Net income (loss)	-47,696,670		23,942,032
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Increase) decrease in commodity futures trading account - cash and cash equivalents	11,654,087		-22,771,705
Unrealized (gain) loss on open futures contracts	-2,972,667		1,482,624
(Increase) decrease in directors' fees and insurance receivable	-55,511		-26,621
(Increase) decrease in ETF transaction fees receivable	1,050		350
Increase (decrease) in management fees payable	-102,432		49,558
Increase (decrease) in professional fees payable	-182,828		-141,334
Increase (decrease) in directors' fees and insurance payable	-15,638		-8,199
Net cash provided by (used in) operating activities	-39,370,609		2,526,705
Cash Flows from Financing Activities:
Addition of shares	39,544,842		42,930,201
Redemption of shares	-227,935,467		0
Net cash provided by (used in) financing activities	-188,390,625		42,930,201
Net Increase (Decrease) in Cash and Cash Equivalents	-227,761,234		45,456,906
Cash and Cash Equivalents, beginning of year	711,984,950		474,123,523
Cash and Cash Equivalents, end of year	484,223,716		519,580,429
United States Copper Index Fund [Member]
Cash Flows from Operating Activities:
Net income (loss)	-118,292		-224,629
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Increase) decrease in commodity futures trading account - cash and cash equivalents	189,634		-264,309
Unrealized (gain) loss on open futures contracts	-247,238		225,900
(Increase) decrease in receivable from Sponsor	32,005		67,521
(Increase) decrease in interest receivable	-1		0
(Increase) decrease in directors' fees and insurance receivable	-233		-142
Increase (decrease) in management fees payable	-605		136
Increase (decrease) in professional fees payable	-23,935		-70,108
Increase (decrease) in directors' fees and insurance payable	-35		-16
Net cash provided by (used in) operating activities	-168,700		-265,647
Cash Flows from Financing Activities:
Addition of shares	0		997,004
Redemption of shares	-893,834		0
Net cash provided by (used in) financing activities	-893,834		997,004
Net Increase (Decrease) in Cash and Cash Equivalents	-1,062,534		731,357
Cash and Cash Equivalents, beginning of year	2,729,373		2,040,735
Cash and Cash Equivalents, end of year	1,666,839		2,772,092
United States Agricultural Index Fund [Member]
Cash Flows from Operating Activities:
Net income (loss)	-208,832		344,131
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Increase) decrease in commodity futures trading account - cash and cash equivalents	6,860		22,186
Unrealized (gain) loss on open futures contracts	35,123		-190,023
(Increase) decrease in receivable from Sponsor	29,241		77,261
(Increase) decrease in directors' fees and insurance receivable	-87		-113
Increase (decrease) in management fees payable	-125		195
Increase (decrease) in professional fees payable	-22,726		-79,950
Increase (decrease) in directors' fees and insurance payable	-104		-52
Net cash provided by (used in) operating activities	-160,650		173,635
Cash Flows from Financing Activities:
Addition of shares	0		0
Redemption of shares	0		0
Net cash provided by (used in) financing activities	0		0
Net Increase (Decrease) in Cash and Cash Equivalents	-160,650		173,635
Cash and Cash Equivalents, beginning of year	2,142,415		2,098,545
Cash and Cash Equivalents, end of year	1,981,765		2,272,180
United States Metals Index Fund [Member]
Cash Flows from Operating Activities:
Net income (loss)	-47,819	[1]	-13,760
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Increase) decrease in commodity futures trading account - cash and cash equivalents	318,156	[1]	15,006
Unrealized (gain) loss on open futures contracts	-136,564	[1]	-22,517
(Increase) decrease in receivable from Sponsor	37,785	[1]	77,582
(Increase) decrease in interest receivable	11	[1]	0
(Increase) decrease in directors' fees and insurance receivable	0	[1]	-142
Increase (decrease) in management fees payable	-1,128	[1]	16
Increase (decrease) in professional fees payable	-38,996	[1]	-80,232
Increase (decrease) in directors' fees and insurance payable	-79	[1]	-36
Net cash provided by (used in) operating activities	131,366	[1]	-24,083
Cash Flows from Financing Activities:
Addition of shares	0	[1]	0
Redemption of shares	-1,933,801	[1]	0
Net cash provided by (used in) financing activities	-1,933,801	[1]	0
Net Increase (Decrease) in Cash and Cash Equivalents	-1,802,435	[1]	-24,083
Cash and Cash Equivalents, beginning of year	1,802,435	[1]	1,918,706
Cash and Cash Equivalents, end of year	$0	[1]	$1,894,623

[1]	USMI ceased trading on the NYSE Arca on March 18, 2015 and the Fund's liquidation date was March 24, 2015.

Organization_And_Business

Organization And Business	3 Months Ended
Organization And Business	Mar. 31, 2015
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, and 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. On January 30, 2015, USCF as the sponsor of the Trust and its series the United States Metals Index Fund (“USMI”) announced that its officers and members had authorized a plan to (i) liquidate USMI, (ii) terminate the continuous offering of USMI, and (iii) deregister USMI under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and therefore, terminate the Trust’s obligation to include USMI on its periodic and current reports with the U.S. Securities and Exchange Commission (“SEC”).

	Shares of USMI ceased trading on the NYSE Arca, Inc. (“NYSE Arca”) and USMI was closed to purchases and redemptions as of the close of regular trading on the NYSE Arca on March 18, 2015 (the “Closing Date”).

	On March 18, 2015, the SEC declared effective a post-effective amendment to the registration statement for USMI to remove from registration all of the securities that remained unsold as of March 18, 2015 (the termination of the offering). USCF, on behalf of the Trust and USMI, terminated USMI effective March 18, 2015. On March 24, 2015, USMI liquidated all its assets and distributed cash pro rata to all remaining shareholders as of such date. On March 31, 2015, the NYSE Arca filed a Form 25 removing the listing of USMI on the NYSE Arca.

	USCI, CPER and USAG each issue shares (“shares”) that may be purchased and sold on the NYSE Arca. USCI, CPER, and USAG 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 shares 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 shares 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 shares 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 and a swaps firm on August 8, 2013. 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 (“USO”), the United States Natural Gas Fund, LP (“UNG”), the United States 12 Month Oil Fund, LP (“USL”), the United States Gasoline Fund, LP (“UGA”) and the United States Diesel-Heating Oil Fund, LP (“UHN”), which listed their limited partnership shares 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 USO’s, UNG’s, USL’s, UGA’s and UHN’s shares commenced trading on the NYSE Arca on November 25, 2008. USCF is also the general partner of the United States Short Oil Fund, LP (“DNO”), the United States 12 Month Natural Gas Fund, LP (“UNL”) and the United States Brent Oil Fund, LP (“BNO”), which listed their limited partnership shares 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.”

	Effective as of May 1, 2012, each of USCI, CPER and USAG issue shares to certain authorized purchasers (“Authorized Participants”) by offering baskets consisting of 50,000 shares (“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 shares to Authorized Participants by offering baskets consisting of 100,000 shares through the Marketing Agent. The purchase price for a Creation Basket is based upon the net asset value (“NAV”) of a share 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 December 31, 2014 (and continuing at least through April 30, 2015), Authorized Participants 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 shares; prior to July 1, 2011, Authorized Participants paid USCI $1,000 for each order placed to create one or more Creation Baskets or to redeem one or more Redemption Baskets. From May 1, 2012 through December 31, 2014 (and continuing at least through April 30, 2015), Authorized Participants pay each of CPER and USAG $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, Authorized Participants paid $1,000 for each order placed to create one or more Creation Baskets or to redeem one or more Redemption Baskets. Shares may be purchased or sold on a nationally recognized securities exchange in smaller increments than a Creation Basket or Redemption Basket. Shares purchased or sold on a nationally recognized securities exchange are not purchased or sold at the per share 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	3 Months Ended
Summary Of Significant Accounting Policies	Mar. 31, 2015
Accounting Policies [Abstract]
Summary Of Significant Accounting Policies	NOTE 2 - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

	Basis of Presentation

	The financial statements have been prepared in conformity with GAAP as detailed in the Financial Accounting Standards Board’s (“FASB”) Accounting Standards Codification. Each Trust Series is an investment company and follows the accounting and reporting guidance in FASB Topic 946.

	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 (‘FCM”) at the 90-day Treasury bill rate. In addition, each Trust Series earns income on funds held at the custodian and/or FCM 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 2011. 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 March 31, 2015 for any Trust Series.

	Trust Capital and Allocation of Income and Losses

	Profit or loss shall be allocated among the shareholders of each Trust Series in proportion to the number of shares 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.

	Creations and Redemptions

	Effective as of May 1, 2012, Authorized Participants may purchase Creation Baskets or redeem Redemption Baskets for USCI, CPER and USAG only in blocks of 50,000 shares at a price equal to the NAV of the shares calculated shortly after the close of the core trading session on the NYSE Arca on the day the order is placed.

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

	Authorized Participants pay each Trust Series a fee of $350 (continuing at least through April 30, 2015) for each order placed to create one or more Creation Baskets or to redeem one or more Redemption Baskets.

	Calculation of Net Asset Value (“NAV”)

	Each Trust Series’ per share 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 shares issued and 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 Share

	Net income (loss) per share is the difference between the per share NAV at the beginning of each period and the per share NAV at the end of each period. The weighted average number of shares outstanding was computed for purposes of disclosing net income (loss) per weighted average share. The weighted average shares are equal to the number of shares outstanding at the end of the period, adjusted proportionately for shares added and redeemed based on the amount of time the shares were outstanding during such period. As of March 31, 2015, USCF held 5 shares of USCI, 40 shares of CPER and 5 shares of USAG.

	Offering Costs

	Offering costs incurred in connection with the registration of shares prior to the commencement of the offering are borne by USCF. Offering costs incurred in connection with the registration of additional shares 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.

	Reclassifications

	Certain prior year amounts have been reclassified to conform to the current year presentation.

	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	3 Months Ended
Trust Series	Mar. 31, 2015
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 shares, USCF received 20 Sponsor Shares 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 shares on Form S-1 with the SEC. On August 10, 2010, USCI listed its shares on the NYSE Arca under the ticker symbol “USCI”. USCI established its initial per share NAV by setting the price at $50.00 and issued 100,000 shares 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 shares be outstanding at the beginning of the trading day on the NYSE Arca, USCF purchased the initial Creation Basket from the initial Authorized Participant at the initial offering price. The $1,000 fee that would otherwise be charged to the Authorized Participant 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 Participant repurchased the shares comprising such basket in accordance with the specified conditions noted above. On September 14, 2011, USCF redeemed the 20 Sponsor Shares of USCI and, on September 19, 2011, USCF purchased five shares 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 Shares 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 Shares of CPER and purchased 40 shares of CPER in the open market. On April 13, 2012, USCF received 40 Sponsor Shares 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 Shares of USAG and on October 3, 2012, purchased 5 shares of USAG on the open market. On June 19, 2012, USCF received 40 Sponsor Shares 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 Shares of USMI and, on September 4, 2013, purchased 5 shares of USMI on the open market. On March 18, 2015 all Sponsor Shares of USMI were redeemed and USMI discontinued trading.

	CPER and USAG received notice of effectiveness from the SEC for its registration of 30,000,000 CPER shares and 20,000,000 USAG shares on September 6, 2011. The order to permit listing CPER and USAG on the NYSE Arca was received on October 20, 2011. On November 15, 2011, CPER listed its shares on the NYSE Arca under the ticker symbol “CPER.” CPER established its initial per share NAV by setting the price at $25 and issued 100,000 shares to the initial Authorized Participant, Merrill Lynch Professional Clearing Corp., 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 Participant 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 shares on the NYSE Arca under the ticker symbol “USAG.” USAG established its initial per share NAV by setting the price at $25. 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 Participants nor were the shares 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.

	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 (“OTC”) 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 shares’ per share net asset value (“NAV”) to reflect the daily changes in percentage terms of the SummerHaven Dynamic Commodity Index Total Return^SM (the “SDCI”), less USCI’s expenses. USCF does not intend to operate USCI in a fashion such that its per share NAV will equal, in dollar terms, the spot prices of the commodities underlying the Benchmark Component Futures Contracts (as defined below) that comprise the SDCI 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 SDCI is designed to reflect the performance of a diversified group of commodities. The SDCI 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 SDCI are referred to herein as “Benchmark Component Futures Contracts.” The SDCI is owned and maintained by SummerHaven Index Management, LLC (“SHIM”) and calculated and published by Bloomberg, L.P. USCI invests first in the current Applicable 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 a Benchmark Component Futures Contract, or may hold Other Commodity-Related Investments that are intended to replicate the return on the Benchmark Component Futures Contracts, but may fail to closely track the SDCI’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 Contracts, 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 shares began trading on August 10, 2010. As of March 31, 2015, USCI held 506 Futures Contracts on the NYMEX, 2,088 Futures Contracts on the ICE Futures, 3,024 Futures Contracts on the CBOT, 979 Futures Contracts on the CME, 6,698 Futures Contracts on the LME and 1,300 Futures Contracts on the COMEX, totaling 14,595 futures contracts.

	CPER’s Investment Objective

	The investment objective of CPER is for the daily changes in percentage terms of its shares’ per share NAV to reflect the daily changes in percentage terms of the SummerHaven Copper Index Total Return^SM (the “SCI”), less CPER’s expenses. USCF does not intend to operate CPER in a fashion such that its per share 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 SCI 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 SCI is designed to reflect the performance of the investment returns from a portfolio of copper futures contracts. The SCI is owned and maintained by SHIM and calculated and published by the NYSE Arca. The SCI 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 SHIM. The Eligible Copper Futures Contracts that at any given time make up the SCI 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 shares began trading on November 15, 2011. As of March 31, 2015, 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 shares’ per share NAV to reflect the daily changes in percentage terms of the SummerHaven Dynamic Agriculture Index Total Return^SM (the “SDAI”), less USAG’s expenses. USCF does not intend to operate USAG in a fashion such that its per share 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 SDAI 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 SDAI is designed to reflect the performance of a diversified group of agricultural commodities. The SDAI is owned and maintained by SHIM and calculated and published by the NYSE Arca. Futures contracts for the agricultural commodities comprising the SDAI 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 SDAI is comprised of 14 Eligible Agriculture Futures Contracts that are selected on a monthly basis based on quantitative formulas developed by SHIM. The Eligible Agriculture Futures Contracts that at any given time make up the SDAI 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 SHIM.

	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 SDAI, 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 SDAI, 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 shares began trading on April 13, 2012. As of March 31, 2015, USAG held 41 Futures Contracts on the ICE Futures, 8 Futures Contracts on the CME, 2 Futures Contract on the KCBT and 31 Futures Contracts on the CBOT, totaling 82 futures contracts.

	Other Defined Terms – Trust Series

	The SDCI, the SCI and the SDAI 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 Condensed 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 Condensed 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 shareholders.

Fees_Paid_By_Each_Trust_Series

Fees Paid By Each Trust Series And Related Party Transactions	3 Months Ended
	Mar. 31, 2015
Fees Paid By Usci and Cper and Related Party Transactions [Abstract]
Fees Paid By Each Trust Series 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 and USAG 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 May 1, 2014 and continuing through December 31, 2015, USCF has contractually agreed to lower the management fee to 0.80% per annum of average daily total net assets for USCI, 0.65% per annum of average daily total net assets for CPER and 0.65% per annum of average daily total net assets for USAG. From May 29, 2012 through April 30, 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.

	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 shares subsequent to the initial offering. These costs include registration or other fees paid to regulatory agencies in connection with the offer and sale of shares, and all legal, accounting, printing and other expenses associated with such offer and sale. During the three months ended March 31, 2015 and 2014, no 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’ fees and directors’ and officers’ liability insurance for such Trust Series and the Related Public Funds. In addition, 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. 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 ended December 31, 2015, are estimated to be a total of $171,174 for the Trust Series and the Related Public Funds. USCI’s portion of such fees and expenses for year ended December 31, 2015 are estimated to be a total of $169,876, CPER’s portion of such fees and expenses for year ended December 31, 2015 are estimated to be a total of $762 and USAG’s portion of such fees and expenses for year ended December 31, 2015 are estimated to be a total of $536.

	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 $690,000 for the year ended December 31, 2015 for USCI, $46,000 for the year ended December 31, 2015 for CPER, and $41,000 for the year ended December 31, 2015 for USAG.

	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– Contracts and Agreements below. In addition, USCF has voluntarily agreed to pay certain expenses normally borne by each of CPER and USAG to the extent that such expenses exceed 0.15% (15 basis points) of each of CPER’s and USAG’s NAV, on an annualized basis, through at least April 30, 2015. USCF has no obligation to continue such payments into subsequent periods. For the three months ended March 31, 2015, USCF waived $10,824 in expenses for CPER and $9,891 for USAG. This voluntary expense waiver is in addition to those amounts USCF is contractually obligated to pay as described in Note 5 – Contracts and Agreements below.

Contracts_And_Agreements

Contracts And Agreements	3 Months Ended
Contracts And Agreements	Mar. 31, 2015
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 website construction and development; which are borne by USCF.

	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 the Related Public Funds’ combined net assets, (b) 0.0465% for the Related Public Funds’ combined net assets greater than $500 million but less than $1 billion, and (c) 0.035% once the Related Public Funds’ 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.

	The Trust on behalf of each Trust Series entered into a brokerage agreement, dated March 1, 2010 for USCI and November 18, 2011 for each of CPER and USAG, as amended from time to time, with Newedge USA, LLC (“Newedge”). On July 7, 2014, the Trust on behalf of each Trust Series entered into a Futures and Cleared Swaps Agreement with Wells Fargo Securities, LLC (“WFS”). WFS and Newedge are collectively referred to as the “FCM”. The agreements require the FCM 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 the FCM for each Trust Series’ account. In accordance with the agreement, the FCM 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 shares 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 shares 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”).

	USCI

		For the three months ended			For the three months ended
		March 31, 2015			March 31, 2014
	Total commissions accrued to brokers	$	199,183		$	101,246
	Total commissions as an annualized percentage of average total net assets		0.12	%		0.08	%
	Commissions accrued as a result of rebalancing	$	181,403		$	98,726
	Percentage of commissions accrued as a result of rebalancing		91.07	%		97.51	%
	Commissions accrued as a result of creation and redemption activity	$	17,780		$	2,520
	Percentage of commissions accrued as a result of creation and redemption activity		8.93	%		2.49	%

	The increase in USCI’s total commissions accrued to brokers for the three months ended March 31, 2015, compared to the three months ended March 31, 2014, was primarily due to an increase in USCI’s total net assets (due to net creations) as well as an increase in the number of contracts traded during the rebalancing period.

	CPER

		For the three months ended			For the three months ended
		March 31, 2015			March 31, 2014
	Total commissions accrued to brokers	$	260		$	368
	Total commissions as an annualized percentage of average total net assets		0.05	%		0.06	%
	Commissions accrued as a result of rebalancing	$	190		$	292
	Percentage of commissions accrued as a result of rebalancing		72.98	%		79.38	%
	Commissions accrued as a result of creation and redemption activity	$	70		$	76
	Percentage of commissions accrued as a result of creation and redemption activity		27.02	%		20.62	%

	CPER’s total commissions accrued to brokers for the three months ended March 31, 2015, compared to the three months ended March 31, 2014, were similar.

	USAG

		For the three months ended			For the three months ended
		March 31, 2015			March 31, 2014
	Total commissions accrued to brokers	$	658		$	401
	Total commissions as an annualized percentage of average total net assets		0.12	%		0.07	%
	Commissions accrued as a result of rebalancing	$	567		$	401
	Percentage of commissions accrued as a result of rebalancing		86.23	%		100	%
	Commissions accrued as a result of creation and redemption activity	$	91		$	—
	Percentage of commissions accrued as a result of creation and redemption activity		13.77	%		—	%

	USAG’s total commissions accrued to brokers for the three months ended March 31, 2015, compared to the three months ended March 31, 2014, were similar.

	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 and USAG, 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 SHIM, 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, 2014, 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	3 Months Ended
	Mar. 31, 2015
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 may engage in trading options on futures contracts and 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 FCM. Additional deposits may be necessary for any loss on contract value. The Commodity Exchange Act requires a FCM to segregate all customer transactions and assets from the FCM’s proprietary activities.

	Futures contracts, options on futures contracts and cleared swaps 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. Buying and selling options on futures contracts exposes investors to the risks of purchasing or selling futures contracts.

	All of the Futures Contracts held by each Trust Series were exchange-traded through March 31, 2015. The risks associated with exchange-traded contracts are generally perceived to be less than those associated with OTC transactions since, in OTC transactions, a party must rely solely on the credit of its respective individual counterparties. When each Trust Series enters into non-exchange traded contracts (including Exchange for Risk or EFR transactions), it is 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 FCM are considered commingled with all other customer funds, subject to the FCM’s segregation requirements. In the event of a FCM’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 FCM could result in the complete loss of a Trust Series’ assets posted with that FCM; 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 FCM. 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 share NAV. Each Trust Series may be exposed to any risk of loss associated with an investment in such money market funds. As of March 31, 2015 and December 31, 2014, 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 March 31, 2015 and December 31, 2014, USCI held cash deposits and investments in Treasuries in the amounts of $552,791,955 and $792,207,276, respectively, with the custodian and FCM. As of March 31, 2015 and December 31, 2014, CPER held cash deposits and investments in Treasuries in the amounts of $1,814,353 and $3,066,521, respectively, with the custodian and FCM. As of March 31, 2015 and December 31, 2014, USAG held cash deposits and investments in Treasuries in the amounts of $2,197,731 and $2,365,241, respectively, with the custodian and FCM. Some or all of these amounts may be subject to loss should the Trust Series’ custodian and/or FCM 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 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	3 Months Ended
Financial Highlights	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Financial Highlights	NOTE 7 – FINANCIAL HIGHLIGHTS

	The following tables present per share performance data and other supplemental financial data for each Trust Series for the three months ended March 31, 2015 and 2014 for the shareholders. This information has been derived from information presented in the condensed financial statements.

	USCI

			For the Three Months Ended			For the Three Months Ended
			March 31, 2015			March 31, 2014
			(Unaudited)			(Unaudited)
	Per Share Operating Performance:
	Net asset value, beginning of period		$	48.24		$	56.06
	Total income (loss)			-3.17			2.7
	Net expenses			-0.13			-0.16
	Net increase (decrease) in net asset value			-3.3			2.54
	Net asset value, end of period		$	44.94		$	58.6

	Total Return			-6.84	%		4.53	%

	Ratios to Average Net Assets
	Total income (loss)			-6.9	%		4.73	%
	Management fees*			0.8	%**		0.95	%
	Total expenses excluding management fees*			0.3	%		0.2	%
	Expenses waived*			—	%**		—	%
	Net expenses excluding management fees*			0.3	%		0.2	%
	Net income (loss)			-7.18	%		4.45	%

	*	Annualized.
	**	Effective May 1, 2014 and continuing through December 31, 2015, USCF has contractually agreed to lower the management fee to 0.80% per annum of average daily total net assets for USCI.

	CPER

			For the Three Months Ended			For the Three Months Ended
			March 31, 2015			March 31, 2014
			(Unaudited)			(Unaudited)
	Per Share Operating Performance:
	Net asset value, beginning of period		$	19.1		$	22.92
	Total income (loss)			-0.52			-2.44
	Net expenses			-0.04			-0.05
	Net increase (decrease) in net asset value			-0.56			-2.49
	Net asset value, end of period		$	18.54		$	20.43

	Total Return			-2.93	%		-10.86	%

	Ratios to Average Net Assets
	Total income (loss)			-5.91	%		-9.53	%
	Management fees*			0.65	%**		0.65	%***
	Total expenses excluding management fees*			2.42	%		2.75	%
	Expenses waived*			-2.27	%**		-2.51	%***
	Net expenses excluding management fees*			0.15	%		0.24	%
	Net income (loss)			-6.11	%		-9.75	%

	*	Annualized.
	**	Effective May 1, 2014 and continuing through December 31, 2015, USCF has contractually agreed to lower the management fee to 0.65% per annum of average daily total net assets for CPER. USCF has voluntarily agreed to pay certain expenses typically borne by CPER to the extent that such expenses exceeded 0.15% (15 basis points) of CPER’s NAV, on an annualized basis, through at least May 1, 2015. USCF has no obligation to continue such payments into subsequent periods.
	***	Effective as of May 29, 2012 through April 30, 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 Three Months Ended			For the Three Months Ended
			March 31, 2015			March 31, 2014
			(Unaudited)			(Unaudited)
	Per Share Operating Performance:
	Net asset value, beginning of period		$	22.97		$	22.79
	Total income (loss)			-2.05			3.5
	Net expenses			-0.04			-0.06
Net increase (decrease) in net asset value			-2.09			3.44
Net asset value, end of period		$	20.88		$	26.23

Total Return			-9.1	%		15.09	%

Ratios to Average Net Assets
Total income (loss)			-9.37	%		14.46	%
Management fees*			0.65	%**		0.8	%***
Total expenses excluding management fees*			2	%†		0.99	%
Expenses waived*			-1.84	%**†		-0.75	%
Net expenses excluding management fees*			0.16	%†		0.24	%
Net income (loss)			9.57	%		14.2	%

*	Annualized
**	Effective May 1, 2014 and continuing through December 31, 2015, USCF has contractually agreed to lower the management fee to 0.65% per annum of average daily total net assets for USAG.
***	Effective as of May 30, 2012 (and continuing through April 30, 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.
†	USCF has voluntarily agreed to pay certain expenses typically borne by USAG to the extent that such expenses exceeded 0.15% (15 basis points) of USAG’s NAV, on an annualized basis, through at least May 1, 2015. USCF has no obligation to continue such payments into subsequent periods.

Total returns are calculated based on the change in value during the period. An individual shareholder’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

3 Months Ended

Mar. 31, 2015

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 March 31, 2015 using the fair value hierarchy:

At March 31, 2015

Total

Level I

Level II

Level III

Short-Term Investments

369,909,971

—

Exchange-Traded Futures Contracts

Foreign Contracts

-31,953,444

—

United States Contracts

-3,341,048

—

During the three months ended March 31, 2015, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USCI’s securities at December 31, 2014 using the fair value hierarchy:

At December 31, 2014

Total

Level I

Level II

Level III

Short-Term Investments

509,916,252

—

Exchange-Traded Futures Contracts

Foreign Contracts

-27,137,120

—

United States Contracts

-11,130,039

—

During year ended December 31, 2014, there were no transfers between Level I and Level II.

The following table summarizes the valuation of CPER’s securities at March 31, 2015 using the fair value hierarchy:

At March 31, 2015

Total

Level I

Level II

Level III

Short-Term Investments

1,399,814

—

Exchange-Traded Futures Contracts

United States Contracts

49,713

—

During the three months ended March 31, 2015, there were no transfers between Level I and Level II.

The following table summarizes the valuation of CPER’s securities at December 31, 2014 using the fair value hierarchy:

At December 31, 2014

Total

Level I

Level II

Level III

Short-Term Investments

1,699,497

—

Exchange-Traded Futures Contracts

United States Contracts

-197,525

—

During the year ended December 31, 2014, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USAG’s securities at March 31, 2015 using the fair value hierarchy:

At March 31, 2015

Total

Level I

Level II

Level III

Short-Term Investments

1,599,744

—

Exchange-Traded Futures Contracts

Foreign Contracts

-93,477

—

United States Contracts

-8,222

—

During the three months ended March 31, 2015, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USAG’s securities at December 31, 2014 using the fair value hierarchy:

At December 31, 2014

Total

Level I

Level II

Level III

Short-Term Investments

1,599,523

—

Exchange-Traded Futures Contracts

Foreign Contracts

-76,062

—

United States Contracts

9,486

—

During the year ended December 31, 2014, 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

Condensed

Derivatives not Accounted for

Statements of Financial

Fair Value

as Hedging Instruments

Condition Location

At March 31, 2015

At December 31, 2014

Futures - Commodity Contracts

Assets

-35,294,492

-38,267,159

Fair Value of Derivative Instruments Held by CPER

Condensed

Derivatives not Accounted for

Statements of Financial

Fair Value

as Hedging Instruments

Condition Location

At March 31, 2015

At December 31, 2014

Futures - Commodity Contracts

Assets

49,713

-197,525

Fair Value of Derivative Instruments Held by USAG

Condensed

Derivatives not Accounted for

Statements of Financial

Fair Value

as Hedging Instruments

Condition Location

At March 31, 2015

At December 31, 2014

Futures - Commodity Contracts

Assets

-101,699

-66,576

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

For the three months ended

March 31, 2015

March 31, 2014

Change in

Derivatives

Location of

Realized

Unrealized

Realized

Unrealized

not Accounted

Gain (Loss)

for as

on Derivatives

Hedging

Recognized

Instruments

in Income

Futures – Commodity

Realized gain

-48,958,657

26,871,173

Contracts

(loss) on closed contracts

Change in unrealized gain (loss) on open contracts

2,972,667

-1,482,624

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

For the three months ended

March 31, 2015

March 31, 2014

Change in

Derivatives

Location of

Realized

Unrealized

Realized

Unrealized

not Accounted

Gain (Loss)

for as

on Derivatives

Hedging

Recognized

Instruments

in Income

Futures – Commodity

Realized gain

-362,375

5,663

Contracts

(loss) on closed contracts

Change in unrealized gain (loss) on open contracts

247,238

-225,900

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

For the three months ended

March 31, 2015

March 31, 2014

Change in

Derivatives

Location of

Realized

Unrealized

Realized

Unrealized

not Accounted

Gain (Loss)

for as

on Derivatives

Hedging

Recognized

Instruments

in Income

Futures – Commodity

Realized gain

-169,684

160,134

Contracts

(loss) on closed contracts

Change in unrealized gain (loss) on open contracts

-35,123

190,023

Subsequent_Events

Subsequent Events	3 Months Ended
Subsequent Events	Mar. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	NOTE 9 – SUBSEQUENT EVENTS

	The Trust and each Trust Series thereunder have performed an evaluation of subsequent events through the date the condensed financial statements were issued. This evaluation did not result in any subsequent events that necessitated disclosures and/or adjustments, other than noted below.

	Mr. Howard Mah, Management Director, Chief Financial Officer (Principal Accounting Officer), Secretary and Treasurer of USCF, sponsor of the United States Commodity Index Funds Trust, tendered his resignation effective May 15, 2015. It is anticipated that Mr. Stuart Crumbaugh, who was hired by USCF on April 6, 2015, will be appointed the Chief Financial Officer (Principal Accounting Officer), Secretary and Treasurer effective on May 15, 2015 (concurrently with the Board of Directors’ accepting Mr. Mah’s resignation).

Summary_Of_Significant_Account1

Summary Of Significant Accounting Policies (Policies)	3 Months Ended
Summary Of Significant Accounting Policies (Policies)	Mar. 31, 2015
Basis of Presentation	Basis of Presentation

	The financial statements have been prepared in conformity with GAAP as detailed in the Financial Accounting Standards Board’s (“FASB”) Accounting Standards Codification. Each Trust Series is an investment company and follows the accounting and reporting guidance in FASB Topic 946.

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 (‘FCM”) at the 90-day Treasury bill rate. In addition, each Trust Series earns income on funds held at the custodian and/or FCM 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 2011. 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 March 31, 2015 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 shareholders of each Trust Series in proportion to the number of shares 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.

Creations and Redemptions	Creations and Redemptions

	Effective as of May 1, 2012, Authorized Participants may purchase Creation Baskets or redeem Redemption Baskets for USCI, CPER and USAG only in blocks of 50,000 shares at a price equal to the NAV of the shares calculated shortly after the close of the core trading session on the NYSE Arca on the day the order is placed.

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

	Authorized Participants pay each Trust Series a fee of $350 (continuing at least through April 30, 2015) for each order placed to create one or more Creation Baskets or to redeem one or more Redemption Baskets.

Calculation of Net Asset Value (bNAVb)	Calculation of Net Asset Value (“NAV”)

	Each Trust Series’ per share 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 shares issued and 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 Share	Net Income (Loss) Per Share

	Net income (loss) per share is the difference between the per share NAV at the beginning of each period and the per share NAV at the end of each period. The weighted average number of shares outstanding was computed for purposes of disclosing net income (loss) per weighted average share. The weighted average shares are equal to the number of shares outstanding at the end of the period, adjusted proportionately for shares added and redeemed based on the amount of time the shares were outstanding during such period. As of March 31, 2015, USCF held 5 shares of USCI, 40 shares of CPER and 5 shares of USAG.

Offering Costs	Offering Costs

	Offering costs incurred in connection with the registration of shares prior to the commencement of the offering are borne by USCF. Offering costs incurred in connection with the registration of additional shares 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.

Reclassifications	Reclassifications

	Certain prior year amounts have been reclassified to conform to the current year presentation.

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.

Contracts_And_Agreements_Table

Contracts And Agreements (Tables)	3 Months Ended
Contracts And Agreements (Tables)	Mar. 31, 2015
Contractors [Abstract]
Brokerage Commissions	USCI

		For the three months ended			For the three months ended
		March 31, 2015			March 31, 2014
	Total commissions accrued to brokers	$	199,183		$	101,246
	Total commissions as an annualized percentage of average total net assets		0.12	%		0.08	%
	Commissions accrued as a result of rebalancing	$	181,403		$	98,726
	Percentage of commissions accrued as a result of rebalancing		91.07	%		97.51	%
	Commissions accrued as a result of creation and redemption activity	$	17,780		$	2,520
	Percentage of commissions accrued as a result of creation and redemption activity		8.93	%		2.49	%


	CPER

		For the three months ended			For the three months ended
		March 31, 2015			March 31, 2014
	Total commissions accrued to brokers	$	260		$	368
	Total commissions as an annualized percentage of average total net assets		0.05	%		0.06	%
	Commissions accrued as a result of rebalancing	$	190		$	292
	Percentage of commissions accrued as a result of rebalancing		72.98	%		79.38	%
	Commissions accrued as a result of creation and redemption activity	$	70		$	76
	Percentage of commissions accrued as a result of creation and redemption activity		27.02	%		20.62	%


	USAG

		For the three months ended			For the three months ended
		March 31, 2015			March 31, 2014
	Total commissions accrued to brokers	$	658		$	401
	Total commissions as an annualized percentage of average total net assets		0.12	%		0.07	%
	Commissions accrued as a result of rebalancing	$	567		$	401
	Percentage of commissions accrued as a result of rebalancing		86.23	%		100	%
	Commissions accrued as a result of creation and redemption activity	$	91		$	—
	Percentage of commissions accrued as a result of creation and redemption activity		13.77	%		—	%

Financial_Highlights_Tables

Financial Highlights (Tables)	3 Months Ended
Financial Highlights (Tables)	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Per Unit Performance Data and Other Supplemental Financial Data for Usci, Cper, Usag and Usmi	The following tables present per share performance data and other supplemental financial data for each Trust Series for the three months ended March 31, 2015 and 2014 for the shareholders. This information has been derived from information presented in the condensed financial statements.

	USCI

			For the Three Months Ended			For the Three Months Ended
			March 31, 2015			March 31, 2014
			(Unaudited)			(Unaudited)
	Per Share Operating Performance:
	Net asset value, beginning of period		$	48.24		$	56.06
	Total income (loss)			-3.17			2.7
	Net expenses			-0.13			-0.16
	Net increase (decrease) in net asset value			-3.3			2.54
	Net asset value, end of period		$	44.94		$	58.6

	Total Return			-6.84	%		4.53	%

	Ratios to Average Net Assets
	Total income (loss)			-6.9	%		4.73	%
	Management fees*			0.8	%**		0.95	%
	Total expenses excluding management fees*			0.3	%		0.2	%
	Expenses waived*			—	%**		—	%
	Net expenses excluding management fees*			0.3	%		0.2	%
	Net income (loss)			-7.18	%		4.45	%

	*	Annualized.
	**	Effective May 1, 2014 and continuing through December 31, 2015, USCF has contractually agreed to lower the management fee to 0.80% per annum of average daily total net assets for USCI.

	CPER

			For the Three Months Ended			For the Three Months Ended
			March 31, 2015			March 31, 2014
			(Unaudited)			(Unaudited)
	Per Share Operating Performance:
	Net asset value, beginning of period		$	19.1		$	22.92
	Total income (loss)			-0.52			-2.44
	Net expenses			-0.04			-0.05
	Net increase (decrease) in net asset value			-0.56			-2.49
	Net asset value, end of period		$	18.54		$	20.43

	Total Return			-2.93	%		-10.86	%

	Ratios to Average Net Assets
	Total income (loss)			-5.91	%		-9.53	%
	Management fees*			0.65	%**		0.65	%***
	Total expenses excluding management fees*			2.42	%		2.75	%
	Expenses waived*			-2.27	%**		-2.51	%***
	Net expenses excluding management fees*			0.15	%		0.24	%
	Net income (loss)			-6.11	%		-9.75	%

	*	Annualized.
	**	Effective May 1, 2014 and continuing through December 31, 2015, USCF has contractually agreed to lower the management fee to 0.65% per annum of average daily total net assets for CPER. USCF has voluntarily agreed to pay certain expenses typically borne by CPER to the extent that such expenses exceeded 0.15% (15 basis points) of CPER’s NAV, on an annualized basis, through at least May 1, 2015. USCF has no obligation to continue such payments into subsequent periods.
	***	Effective as of May 29, 2012 through April 30, 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 Three Months Ended			For the Three Months Ended
			March 31, 2015			March 31, 2014
			(Unaudited)			(Unaudited)
	Per Share Operating Performance:
	Net asset value, beginning of period		$	22.97		$	22.79
	Total income (loss)			-2.05			3.5
	Net expenses			-0.04			-0.06
	Net increase (decrease) in net asset value			-2.09			3.44
	Net asset value, end of period		$	20.88		$	26.23

Total Return			-9.1	%		15.09	%

Ratios to Average Net Assets
Total income (loss)			-9.37	%		14.46	%
Management fees*			0.65	%**		0.8	%***
Total expenses excluding management fees*			2	%†		0.99	%
Expenses waived*			-1.84	%**†		-0.75	%
Net expenses excluding management fees*			0.16	%†		0.24	%
Net income (loss)			9.57	%		14.2	%

*	Annualized
**	Effective May 1, 2014 and continuing through December 31, 2015, USCF has contractually agreed to lower the management fee to 0.65% per annum of average daily total net assets for USAG.
***	Effective as of May 30, 2012 (and continuing through April 30, 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.
†	USCF has voluntarily agreed to pay certain expenses typically borne by USAG to the extent that such expenses exceeded 0.15% (15 basis points) of USAG’s NAV, on an annualized basis, through at least May 1, 2015. USCF has no obligation to continue such payments into subsequent periods.

Fair_Value_Of_Financial_Instru1

Fair Value Of Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2015

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 March 31, 2015 using the fair value hierarchy:

At March 31, 2015

Total

Level I

Level II

Level III

Short-Term Investments

369,909,971

—

Exchange-Traded Futures Contracts

Foreign Contracts

-31,953,444

—

United States Contracts

-3,341,048

—

During the three months ended March 31, 2015, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USCI’s securities at December 31, 2014 using the fair value hierarchy:

At December 31, 2014

Total

Level I

Level II

Level III

Short-Term Investments

509,916,252

—

Exchange-Traded Futures Contracts

Foreign Contracts

-27,137,120

—

United States Contracts

-11,130,039

—

During year ended December 31, 2014, there were no transfers between Level I and Level II.

The following table summarizes the valuation of CPER’s securities at March 31, 2015 using the fair value hierarchy:

At March 31, 2015

Total

Level I

Level II

Level III

Short-Term Investments

1,399,814

—

Exchange-Traded Futures Contracts

United States Contracts

49,713

—

During the three months ended March 31, 2015, there were no transfers between Level I and Level II.

The following table summarizes the valuation of CPER’s securities at December 31, 2014 using the fair value hierarchy:

At December 31, 2014

Total

Level I

Level II

Level III

Short-Term Investments

1,699,497

—

Exchange-Traded Futures Contracts

United States Contracts

-197,525

—

During the year ended December 31, 2014, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USAG’s securities at March 31, 2015 using the fair value hierarchy:

At March 31, 2015

Total

Level I

Level II

Level III

Short-Term Investments

1,599,744

—

Exchange-Traded Futures Contracts

Foreign Contracts

-93,477

—

United States Contracts

-8,222

—

During the three months ended March 31, 2015, there were no transfers between Level I and Level II.

The following table summarizes the valuation of USAG’s securities at December 31, 2014 using the fair value hierarchy:

At December 31, 2014

Total

Level I

Level II

Level III

Short-Term Investments

1,599,523

—

Exchange-Traded Futures Contracts

Foreign Contracts

-76,062

—

United States Contracts

9,486

—

During the year ended December 31, 2014, there were no transfers between Level I and Level II.

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

Fair Value of Derivative Instruments Held by USCI

Condensed

Derivatives not Accounted for

Statements of Financial

Fair Value

as Hedging Instruments

Condition Location

At March 31, 2015

At December 31, 2014

Futures - Commodity Contracts

Assets

-35,294,492

-38,267,159

Fair Value of Derivative Instruments Held by CPER

Condensed

Derivatives not Accounted for

Statements of Financial

Fair Value

as Hedging Instruments

Condition Location

At March 31, 2015

At December 31, 2014

Futures - Commodity Contracts

Assets

49,713

-197,525

Fair Value of Derivative Instruments Held by USAG

Condensed

Derivatives not Accounted for

Statements of Financial

Fair Value

as Hedging Instruments

Condition Location

At March 31, 2015

At December 31, 2014

Futures - Commodity Contracts

Assets

-101,699

-66,576

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 three months ended

March 31, 2015

March 31, 2014

Change in

Derivatives

Location of

Realized

Unrealized

Realized

Unrealized

not Accounted

Gain (Loss)

for as

on Derivatives

Hedging

Recognized

Instruments

in Income

Futures – Commodity

Realized gain

-48,958,657

26,871,173

Contracts

(loss) on closed contracts

Change in unrealized gain (loss) on open contracts

2,972,667

-1,482,624

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

For the three months ended

March 31, 2015

March 31, 2014

Change in

Derivatives

Location of

Realized

Unrealized

Realized

Unrealized

not Accounted

Gain (Loss)

for as

on Derivatives

Hedging

Recognized

Instruments

in Income

Futures – Commodity

Realized gain

-362,375

5,663

Contracts

(loss) on closed contracts

Change in unrealized gain (loss) on open contracts

247,238

-225,900

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

For the three months ended

March 31, 2015

March 31, 2014

Change in

Derivatives

Location of

Realized

Unrealized

Realized

Unrealized

not Accounted

Gain (Loss)

for as

on Derivatives

Hedging

Recognized

Instruments

in Income

Futures – Commodity

Realized gain

-169,684

160,134

Contracts

(loss) on closed contracts

Change in unrealized gain (loss) on open contracts

-35,123

190,023

Organization_And_Business_Addi

Organization And Business (Additional Information) (Details)	Mar. 31, 2015	Nov. 10, 2010	Aug. 10, 2010	Nov. 15, 2011	Apr. 13, 2012
Redemption Baskets [Member] \| Prior to May 1, 2012 [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
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
United States Commodity Index Fund [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
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	1,000
United States Commodity Index Fund [Member] \| Creation Baskets [Member] \| Effective as of May 1, 2012 [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of Units per basket	50,000
United States Commodity Index Fund [Member] \| Marketing Agent [Member] \| Prior to May 1, 2012 [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of Units per basket	100,000
United States Commodity Index Fund [Member] \| Redemption Baskets [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Fee paid by Authorized Purchasers for each order placed to create one or more Creation Baskets or to redeem one or more baskets	350
United States Commodity Index Fund [Member] \| Redemption Baskets [Member] \| Effective as of May 1, 2012 [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of Units per basket	350
United States Copper Index Fund [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
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
United States Copper Index Fund [Member] \| Creation Baskets [Member] \| Effective as of May 1, 2012 [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of Units per basket	50,000
United States Copper Index Fund [Member] \| Marketing Agent [Member] \| Prior to May 1, 2012 [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of Units per basket	100,000
United States Copper Index Fund [Member] \| Redemption Baskets [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Fee paid by Authorized Purchasers for each order placed to create one or more Creation Baskets or to redeem one or more baskets	350
United States Copper Index Fund [Member] \| Redemption Baskets [Member] \| Effective as of May 1, 2012 [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of Units per basket	350
United States Agriculture Index Fund [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
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
United States Agriculture Index Fund [Member] \| Creation Baskets [Member] \| Effective as of May 1, 2012 [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of Units per basket	50,000
United States Agriculture Index Fund [Member] \| Marketing Agent [Member] \| Prior to May 1, 2012 [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of Units per basket	100,000
United States Agriculture Index Fund [Member] \| Redemption Baskets [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Fee paid by Authorized Purchasers for each order placed to create one or more Creation Baskets or to redeem one or more baskets	350
United States Agriculture Index Fund [Member] \| Redemption Baskets [Member] \| Effective as of May 1, 2012 [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of Units per basket	350

Summary_Of_Significant_Account2

Summary Of Significant Accounting Policies (Additional Information) (Details)	3 Months Ended
	Mar. 31, 2015
Significant Accounting Policies [Line Items]
Minimum likelihood of tax benefits being recognized upon ultimate settlement	50.00%
Cash equivalents maturity period	6 months
United States Commodity Index Fund [Member]
Significant Accounting Policies [Line Items]
Weighted average shares outstanding	5
United States Copper Index Fund [Member]
Significant Accounting Policies [Line Items]
Weighted average shares outstanding	40
United States Agriculture Index Fund [Member]
Significant Accounting Policies [Line Items]
Weighted average shares outstanding	5
Creation Baskets [Member] \| Effective as of May 1, 2012 [Member] \| United States Commodity Index Fund [Member]
Significant Accounting Policies [Line Items]
Number of Units per basket	50,000
Creation Baskets [Member] \| Effective as of May 1, 2012 [Member] \| United States Copper Index Fund [Member]
Significant Accounting Policies [Line Items]
Number of Units per basket	50,000
Creation Baskets [Member] \| Effective as of May 1, 2012 [Member] \| United States Agriculture Index Fund [Member]
Significant Accounting Policies [Line Items]
Number of Units per basket	50,000
Redemption Baskets [Member] \| Effective as of May 1, 2012 [Member] \| United States Commodity Index Fund [Member]
Significant Accounting Policies [Line Items]
Number of Units per basket	350
Redemption Baskets [Member] \| Effective as of May 1, 2012 [Member] \| United States Copper Index Fund [Member]
Significant Accounting Policies [Line Items]
Number of Units per basket	350
Redemption Baskets [Member] \| Effective as of May 1, 2012 [Member] \| United States Agriculture Index Fund [Member]
Significant Accounting Policies [Line Items]
Number of Units per basket	350

Trust_Series_Additional_Inform

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

1 Months Ended

3 Months Ended

0 Months Ended

1 Months Ended

0 Months Ended

Sep. 19, 2011

Dec. 21, 2009

Mar. 31, 2015

Aug. 10, 2010

Jul. 30, 2010

Sep. 06, 2011

Nov. 15, 2011

Dec. 31, 2014

Mar. 31, 2014

Dec. 31, 2013

Nov. 10, 2010

Apr. 13, 2012

Capital Unit [Line Items]

Sponsor capital contribution

$1,000

Capital contribution to trust series

1,000

Units acquisition

Partner sponsor units description

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 Shares 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 Shares of CPER and purchased 40 shares of CPER in the open market. On April 13, 2012, USCF received 40 Sponsor Shares 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 Shares of USAG and on October 3, 2012, purchased 5 shares of USAG on the open market. On June 19, 2012, USCF received 40 Sponsor Shares 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 Shares of USMI and, on September 4, 2013, purchased 5 shares of USMI on the open market.

United States Commodity Index Fund [Member]

Capital Unit [Line Items]

Sponsor capital contribution

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

50,000,000

Commenced investment operations date

10-Aug-10

Initial offering price per unit NAV

$44.94

$50

$48.24

$58.60

$56.06

Number of units issued

100,000

Value of unit issued

5,000,000

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

United States Commodity Index Fund [Member] | Futures Contracts [Member]

Capital Unit [Line Items]

Future contract held

14,595

United States Commodity Index Fund [Member] | Futures Contracts [Member] | NYMEX [Member]

Capital Unit [Line Items]

Future contract held

506

United States Commodity Index Fund [Member] | Futures Contracts [Member] | Ice Futures [Member]

Capital Unit [Line Items]

Future contract held

2,088

United States Commodity Index Fund [Member] | Futures Contracts [Member] | Chicago Board of Trade [Member]

Capital Unit [Line Items]

Future contract held

3,024

United States Commodity Index Fund [Member] | Futures Contracts [Member] | Chicago Mercantile Exchange [Member]

Capital Unit [Line Items]

Future contract held

979

United States Commodity Index Fund [Member] | Futures Contracts [Member] | London Metal Exchange [Member]

Capital Unit [Line Items]

Future contract held

6,698

United States Commodity Index Fund [Member] | Futures Contracts [Member] | Commodity Exchange Inc [Member]

Capital Unit [Line Items]

Future contract held

1,300

United States Commodity Index Fund [Member] | Futures Contracts [Member] | SummerHaven Indexing [Member]

Capital Unit [Line Items]

Future contract held

United States Agriculture Index Fund [Member]

Capital Unit [Line Items]

Sponsor capital contribution

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

20,000,000

Initial offering price per unit NAV

$20.88

$22.97

$26.23

$22.79

$25

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

United States Agriculture Index Fund [Member] | Futures Contracts [Member]

Capital Unit [Line Items]

Future contract held

United States Agriculture Index Fund [Member] | Futures Contracts [Member] | Ice Futures [Member]

Capital Unit [Line Items]

Future contract held

United States Agriculture Index Fund [Member] | Futures Contracts [Member] | Chicago Board of Trade [Member]

Capital Unit [Line Items]

Future contract held

United States Agriculture Index Fund [Member] | Futures Contracts [Member] | Chicago Mercantile Exchange [Member]

Capital Unit [Line Items]

Future contract held

United States Agriculture Index Fund [Member] | Futures Contracts [Member] | Kansas City Board Of Trade [Member]

Capital Unit [Line Items]

Future contract held

United States Metals Index Fund [Member]

Capital Unit [Line Items]

Sponsor capital contribution

[1]

3,000

Initial offering price per unit NAV

[1]

$19.82

[1]

United States Copper Index Fund [Member]

Capital Unit [Line Items]

Sponsor capital contribution

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

30,000,000

Initial offering price per unit NAV

$18.54

$25

$19.10

$20.43

$22.92

Number of units issued

100,000

Value of unit issued

$2,500,000

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

[1]

USMI ceased trading on the NYSE Arca on March 18, 2015 and the Fund's liquidation date was March 24, 2015.

Fees_Paid_By_Each_Trust_Series1

Fees Paid By Each Trust Series And Related Party Transactions (Additional Information) (Details) (USD $)	3 Months Ended			12 Months Ended
	Mar. 31, 2015		Mar. 31, 2014	Dec. 31, 2015
Fees Paid and Related Party Transactions [Line Items]
Trustee annual fee	$3,000
Noninterest Expense Directors Fees	27,884		31,130
Expense waiver	29,608		23,362
Directors and Officers Liability Insurance [Member] \| Subsequent Event [Member]
Fees Paid and Related Party Transactions [Line Items]
Noninterest Expense Directors Fees				171,174
United States Commodity Index Fund [Member]
Fees Paid and Related Party Transactions [Line Items]
Noninterest Expense Directors Fees	27,613		30,717
Estimated investor tax reporting cost	690,000
United States Commodity Index Fund [Member] \| Subsequent Event [Member]
Fees Paid and Related Party Transactions [Line Items]
Noninterest Expense Directors Fees				169,876
United States Commodity Index Fund [Member] \| Effective May 1, 2014 [Member]
Fees Paid and Related Party Transactions [Line Items]
Percentage of average daily net assets paid	0.80%
United States Copper Index Fund [Member]
Fees Paid and Related Party Transactions [Line Items]
Noninterest Expense Directors Fees	99		136
Estimated investor tax reporting cost	46,000
Costs and expenses annual limit for reimbursement	0.15%
Expense waiver	10,824		14,268
United States Copper Index Fund [Member] \| Effective as of May 29, 2012 [Member]
Fees Paid and Related Party Transactions [Line Items]
Percentage of average daily net assets paid	0.95%
United States Copper Index Fund [Member] \| Effective May 1, 2014 [Member]
Fees Paid and Related Party Transactions [Line Items]
Percentage of average daily net assets paid	0.95%
United States Copper Index Fund [Member] \| Directors and Officers Liability Insurance [Member] \| Subsequent Event [Member]
Fees Paid and Related Party Transactions [Line Items]
Noninterest Expense Directors Fees				762
United States Agriculture Index Fund [Member]
Fees Paid and Related Party Transactions [Line Items]
Noninterest Expense Directors Fees	101		141
Estimated investor tax reporting cost	41,000
Expense waiver	9,891		4,511
United States Agriculture Index Fund [Member] \| Effective as of May 29, 2012 [Member]
Fees Paid and Related Party Transactions [Line Items]
Percentage of average daily net assets paid	0.65%
United States Agriculture Index Fund [Member] \| Effective May 1, 2014 [Member]
Fees Paid and Related Party Transactions [Line Items]
Percentage of average daily net assets paid	0.65%
United States Agriculture Index Fund [Member] \| Directors and Officers Liability Insurance [Member] \| Subsequent Event [Member]
Fees Paid and Related Party Transactions [Line Items]
Noninterest Expense Directors Fees				536
United States Metals Index Fund [Member]
Fees Paid and Related Party Transactions [Line Items]
Noninterest Expense Directors Fees	71	[1]	136
Expense waiver	$8,893	[1]	$4,583
United States Metals Index Fund [Member] \| Effective as of May 29, 2012 [Member]
Fees Paid and Related Party Transactions [Line Items]
Percentage of average daily net assets paid	0.80%

[1]	USMI ceased trading on the NYSE Arca on March 18, 2015 and the Fund's liquidation date was March 24, 2015.

Contracts_And_Agreements_Broke

Contracts And Agreements (Brokerage Commission) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions	$200,410		$102,209
United States Commodity Index Fund [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions	199,183		101,246
United States Commodity Index Fund [Member] \| Rebalancing Investments Transaction [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions	181,403		98,726
Brokerage commissions as a percentage of average daily net assets	91.07%		97.51%
United States Commodity Index Fund [Member] \| Creation and Redemption Activity [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions	17,780		2,520
Brokerage commissions as a percentage of average daily net assets	8.93%		2.49%
United States Commodity Index Fund [Member] \| Commission [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions as a percentage of average daily net assets	0.12%		0.08%
United States Copper Index Fund [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions	260		368
United States Copper Index Fund [Member] \| Rebalancing Investments Transaction [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions	190		292
Brokerage commissions as a percentage of average daily net assets	72.98%		79.38%
United States Copper Index Fund [Member] \| Creation and Redemption Activity [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions	70		76
Brokerage commissions as a percentage of average daily net assets	27.02%		20.62%
United States Copper Index Fund [Member] \| Commission [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions as a percentage of average daily net assets	0.05%		0.06%
United States Agriculture Index Fund [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions	658		401
United States Agriculture Index Fund [Member] \| Rebalancing Investments Transaction [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions	567		401
Brokerage commissions as a percentage of average daily net assets	86.23%		100.00%
United States Agriculture Index Fund [Member] \| Creation and Redemption Activity [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions	91		0
Brokerage commissions as a percentage of average daily net assets	13.77%		0.00%
United States Agriculture Index Fund [Member] \| Commission [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions as a percentage of average daily net assets	0.12%		0.07%
United States Metals Index Fund [Member]
Long Duration Contracts Assumptions By Product and Guarantee [Line Items]
Brokerage commissions	$309	[1]	$194

[1]	USMI ceased trading on the NYSE Arca on March 18, 2015 and the Fund's liquidation date was March 24, 2015.

Contracts_And_Agreements_Addit

Contracts And Agreements (Additional Information) (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Annual transfer agency services fee	$20,000
Management fee description	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 and USAG, 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.
Licensing Agreements [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Annual licensing fee		15,000
Management fee paid to SummerHaven by USCF		annual fee of 0.06% of the average daily total net assets of each Trust Series.
Maximum [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Transaction fees per transaction	15
Commissions per round-turn trade, including applicable exchange and NFA fees for Futures Contracts and options on Futures Contracts	15
Minimum [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Base amount for determining fee percentage	75,000
Transaction fees per transaction	7
Commissions per round-turn trade, including applicable exchange and NFA fees for Futures Contracts and options on Futures Contracts	7
For the first $500 million [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Fee percentage	0.06%
For the first $500 million [Member] \| Maximum [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Base amount for determining fee percentage	500,000,000
Combined net assets greater than $500 million but less than $1 billion [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Fee percentage	0.05%
Combined net assets greater than $500 million but less than $1 billion [Member] \| Maximum [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Base amount for determining fee percentage	1,000,000,000
Combined net assets greater than $500 million but less than $1 billion [Member] \| Minimum [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Base amount for determining fee percentage	500,000,000
Combined net assets exceed $1 billion [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Fee percentage	0.04%
Combined net assets exceed $1 billion [Member] \| Minimum [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Base amount for determining fee percentage	1,000,000,000
Marketing Agreement [Member] \| Maximum [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Fee percentage	10.00%
Marketing Agreement [Member] \| Minimum [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Fee percentage	0.04%
Marketing Agreement [Member] \| On each Trust Series' assets up to 3 billion [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Fee percentage	0.06%
Marketing Agreement [Member] \| On each Trust Series' assets up to 3 billion [Member] \| Maximum [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Base amount for determining fee percentage	3,000,000,000
Marketing Agreement [Member] \| On each Trust Series' assets in excess of $3 billion [Member] \| Maximum [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Base amount for determining fee percentage	$3,000,000,000

Financial_Instruments_OffBalan1

Financial Instruments, Off-Balance Sheet Risks and Contingencies (Additional Information) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
United States Commodity Index Fund [Member]
Carrying Amounts and Fair Values of Financial Instruments or Liabilities [Line Items]
Cash deposits and investments in Treasuries	$552,791,955	$792,207,276
United States Copper Index Fund [Member]
Carrying Amounts and Fair Values of Financial Instruments or Liabilities [Line Items]
Cash deposits and investments in Treasuries	1,814,353	3,066,521
United States Agriculture Index Fund [Member]
Carrying Amounts and Fair Values of Financial Instruments or Liabilities [Line Items]
Cash deposits and investments in Treasuries	$2,197,731	$2,365,241

Financial_Highlights_Per_Unit_

Financial Highlights (Per Unit Performance Data and Other Supplemental Financial Data) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014		Aug. 10, 2010	Nov. 15, 2011	Apr. 13, 2012
United States Commodity Index Fund [Member]
Per Share Operating Performance:
Net asset value, beginning of period	$48.24		$56.06		$50
Total income (loss)	($3.17)		$2.70
Net expenses	($0.13)		($0.16)
Net increase (decrease) in net asset value	($3.30)		$2.54
Net asset value, end of period	$44.94		$58.60		$50
Total Return	-6.84%		4.53%
Ratios to Average Net Assets
Total income (loss)	-6.90%		4.73%
Management fees	0.80%	[1],[2]	0.95%	[1]
Total expenses excluding management fees	0.30%	[1]	0.20%	[1]
Expenses waived	0.00%	[1],[2]	0.00%	[1]
Net expenses excluding management fees	0.30%	[1]	0.20%	[1]
Net income (loss)	-7.18%		4.45%
United States Copper Index Fund [Member]
Per Share Operating Performance:
Net asset value, beginning of period	$19.10		$22.92			$25
Total income (loss)	($0.52)		($2.44)
Net expenses	($0.04)		($0.05)
Net increase (decrease) in net asset value	($0.56)		($2.49)
Net asset value, end of period	$18.54		$20.43			$25
Total Return	-2.93%		-10.86%
Ratios to Average Net Assets
Total income (loss)	-5.91%		-9.53%
Management fees	0.65%	[1],[3]	0.65%	[1],[4]
Total expenses excluding management fees	2.42%	[1]	2.75%	[1]
Expenses waived	-2.27%	[1],[3]	-2.51%	[1],[4]
Net expenses excluding management fees	0.15%	[1]	0.24%	[1]
Net income (loss)	-6.11%		-9.75%
United States Agriculture Index Fund [Member]
Per Share Operating Performance:
Net asset value, beginning of period	$22.97		$22.79				$25
Total income (loss)	($2.05)		$3.50
Net expenses	($0.04)		($0.06)
Net increase (decrease) in net asset value	($2.09)		$3.44
Net asset value, end of period	$20.88		$26.23				$25
Total Return	-9.10%		15.09%
Ratios to Average Net Assets
Total income (loss)	-9.37%		14.46%
Management fees	0.65%	[1],[5]	0.80%	[1],[6]
Total expenses excluding management fees	2.00%	[1],[7]	0.99%	[1]
Expenses waived	-1.84%	[1],[5],[7]	-0.75%	[1]
Net expenses excluding management fees	0.16%	[1],[7]	0.24%	[1]
Net income (loss)	9.57%		14.20%

[1]	Annualized.
[2]	Effective May 1, 2014 and continuing through December 31, 2015, USCF has contractually agreed to lower the management fee to 0.80% per annum of average daily total net assets for USCI.
[3]	Effective May 1, 2014 and continuing through December 31, 2015, USCF has contractually agreed to lower the management fee to 0.65% per annum of average daily total net assets for CPER. USCF has voluntarily agreed to pay certain expenses typically borne by CPER to the extent that such expenses exceeded 0.15% (15 basis points) of CPERbs NAV, on an annualized basis, through at least May 1, 2015. USCF has no obligation to continue such payments into subsequent periods.
[4]	Effective as of May 29, 2012 through April 30, 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 May 1, 2014 and continuing through December 31, 2015, USCF has contractually agreed to lower the management fee to 0.65% per annum of average daily total net assets for USAG.
[6]	Effective as of May 30, 2012 (and continuing through April 30, 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.
[7]	USCF has voluntarily agreed to pay certain expenses typically borne by USAG to the extent that such expenses exceeded 0.15% (15 basis points) of USAGbs NAV, on an annualized basis, through at least May 1, 2015. USCF has no obligation to continue such payments into subsequent periods.

Financial_Highlights_Per_Unit_1

Financial Highlights (Per Unit Performance Data and Other Supplemental Financial Data) (Parenthetical) (Details)	3 Months Ended				23 Months Ended
	Mar. 31, 2015		Mar. 31, 2014		Apr. 30, 2014	Apr. 30, 2014
United States Copper Index Fund [Member]
Average Sales Price and Production Costs Per Unit of Production [Line Items]
Percentage of average daily net assets paid monthly, waiver expense	2.27%	[1],[2]	2.51%	[1],[3]
United States Copper Index Fund [Member] \| Maximum [Member]
Average Sales Price and Production Costs Per Unit of Production [Line Items]
Percentage of average daily net assets paid monthly, waiver expense					0.95%
United States Copper Index Fund [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%
United States Agriculture Index Fund [Member]
Average Sales Price and Production Costs Per Unit of Production [Line Items]
Percentage of average daily net assets paid monthly, waiver expense	1.84%	[1],[4],[5]	0.75%	[1]
United States Agriculture Index Fund [Member] \| Maximum [Member]
Average Sales Price and Production Costs Per Unit of Production [Line Items]
Percentage of average daily net assets paid monthly, waiver expense						0.95%
United States Agriculture Index Fund [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						0.80%

[1]	Annualized.
[2]	Effective May 1, 2014 and continuing through December 31, 2015, USCF has contractually agreed to lower the management fee to 0.65% per annum of average daily total net assets for CPER. USCF has voluntarily agreed to pay certain expenses typically borne by CPER to the extent that such expenses exceeded 0.15% (15 basis points) of CPERbs NAV, on an annualized basis, through at least May 1, 2015. USCF has no obligation to continue such payments into subsequent periods.
[3]	Effective as of May 29, 2012 through April 30, 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.
[4]	Effective May 1, 2014 and continuing through December 31, 2015, USCF has contractually agreed to lower the management fee to 0.65% per annum of average daily total net assets for USAG.
[5]	USCF has voluntarily agreed to pay certain expenses typically borne by USAG to the extent that such expenses exceeded 0.15% (15 basis points) of USAGbs NAV, on an annualized basis, through at least May 1, 2015. USCF has no obligation to continue such payments into subsequent periods.

Fair_Value_Of_Financial_Instru2

Fair Value Of Financial Instruments (Valuation of Securities Using Fair Value Hierarchy) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
United States Commodity Index Fund [Member] \| Short-Term Investments [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	$369,909,971	$509,916,252
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	-31,953,444	-27,137,120
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	-3,341,048	-11,130,039
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	369,909,971	509,916,252
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	-31,953,444	-27,137,120
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	-3,341,048	-11,130,039
United States Commodity Index Fund [Member] \| Fair Value, Inputs, Level 2 [Member] \| Short-Term Investments [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Commodity Index Fund [Member] \| Fair Value, Inputs, Level 2 [Member] \| Exchange-Traded Futures Contracts [Member] \| Foreign [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Commodity Index Fund [Member] \| Fair Value, Inputs, Level 2 [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Commodity Index Fund [Member] \| Fair Value, Inputs, Level 3 [Member] \| Short-Term Investments [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Commodity Index Fund [Member] \| Fair Value, Inputs, Level 3 [Member] \| Exchange-Traded Futures Contracts [Member] \| Foreign [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Commodity Index Fund [Member] \| Fair Value, Inputs, Level 3 [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Copper Index Fund [Member] \| Short-Term Investments [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	1,399,814	1,699,497
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	49,713	-197,525
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	1,399,814	1,699,497
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	49,713	-197,525
United States Copper Index Fund [Member] \| Fair Value, Inputs, Level 2 [Member] \| Short-Term Investments [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Copper Index Fund [Member] \| Fair Value, Inputs, Level 2 [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Copper Index Fund [Member] \| Fair Value, Inputs, Level 3 [Member] \| Short-Term Investments [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Copper Index Fund [Member] \| Fair Value, Inputs, Level 3 [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Agriculture Index Fund [Member] \| Short-Term Investments [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	1,599,744	1,599,523
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	-93,477	-76,062
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	-8,222	9,486
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	1,599,744	1,599,523
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	-93,477	-76,062
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	-8,222	9,486
United States Agriculture Index Fund [Member] \| Fair Value, Inputs, Level 2 [Member] \| Short-Term Investments [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Agriculture Index Fund [Member] \| Fair Value, Inputs, Level 2 [Member] \| Exchange-Traded Futures Contracts [Member] \| Foreign [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Agriculture Index Fund [Member] \| Fair Value, Inputs, Level 2 [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Agriculture Index Fund [Member] \| Fair Value, Inputs, Level 3 [Member] \| Short-Term Investments [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Agriculture Index Fund [Member] \| Fair Value, Inputs, Level 3 [Member] \| Exchange-Traded Futures Contracts [Member] \| Foreign [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	0	0
United States Agriculture Index Fund [Member] \| Fair Value, Inputs, Level 3 [Member] \| Exchange-Traded Futures Contracts [Member] \| United States [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	$0	$0

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 $)	Mar. 31, 2015	Dec. 31, 2014
United States Commodity Index Fund [Member]
Derivatives, Fair Value [Line Items]
Derivatives not Accounted for as Hedging Instruments	($35,294,492)	($38,267,159)
United States Copper Index Fund [Member]
Derivatives, Fair Value [Line Items]
Derivatives not Accounted for as Hedging Instruments	49,713	-197,525
United States Agriculture Index Fund [Member]
Derivatives, Fair Value [Line Items]
Derivatives not Accounted for as Hedging Instruments	($101,699)	($66,576)

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
	Mar. 31, 2015		Mar. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Realized Loss on Derivatives Recognized in Income	($49,673,132)		$27,005,397
Change in Unrealized Loss on Derivatives Recognized in Income	3,321,346		-1,495,984
United States Commodity Index Fund [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized Loss on Derivatives Recognized in Income	-48,958,657		26,871,173
Change in Unrealized Loss on Derivatives Recognized in Income	2,972,667		-1,482,624
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 Loss on Derivatives Recognized in Income	-48,958,657		26,871,173
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 Loss on Derivatives Recognized in Income	2,972,667		-1,482,624
United States Copper Index Fund [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized Loss on Derivatives Recognized in Income	-362,375		5,663
Change in Unrealized Loss on Derivatives Recognized in Income	247,238		-225,900
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 Loss on Derivatives Recognized in Income	-362,375		5,663
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 Loss on Derivatives Recognized in Income	247,238		-225,900
United States Agriculture Index Fund [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized Loss on Derivatives Recognized in Income	-169,684		160,134
Change in Unrealized Loss on Derivatives Recognized in Income	-35,123		190,023
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 Loss on Derivatives Recognized in Income	-169,684		160,134
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 Loss on Derivatives Recognized in Income	-35,123		190,023
United States Metals Index Fund [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized Loss on Derivatives Recognized in Income	($182,416)	[1]	($31,573)

[1]	USMI ceased trading on the NYSE Arca on March 18, 2015 and the Fund's liquidation date was March 24, 2015.