United States Copper Index Fund (CPER) 10-Q9 May 192019 Q1 Quarterly reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2019	May 06, 2019
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Entity Registrant Name	United States Commodity Index Funds Trust
Entity Central Index Key	0001479247
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Trading Symbol	USCI
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding		11,550,000
United States Commodity Index Fund [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		10,700,000
United States Copper Index Fund [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		850,000

Condensed Statements of Financi

Condensed Statements of Financial Condition - USD ($)	Mar. 31, 2019	Dec. 31, 2018
United States Commodity Index Fund [Member]
Assets
Cash and cash equivalents	$ 403,949,418	$ 427,657,030
Equity in trading accounts:
Cash and cash equivalents	35,952,692	50,852,183
Unrealized gain (loss) on open commodity futures contracts	3,662,119	(14,487,984)
Dividends receivable	50,505	9,983
Interest receivable	490	4,224
Directors' fees and insurance receivable	15,752	22,319
Total assets	443,630,976	464,057,755
Liabilities and Capital
Payable due to Broker	4,319,226	0
Management fees payable (Note 4)	302,975	367,646
Professional fees payable	393,371	604,296
Brokerage commissions payable	43,305	43,305
Total liabilities	5,058,877	1,015,247
Commitments and Contingencies (Notes 4, 5 and 6)
Capital
Sponsor	0	0
Shareholders	438,572,099	463,042,508
Total Capital	438,572,099	463,042,508
Total liabilities and capital	$ 443,630,976	$ 464,057,755
Shares outstanding	11,300,000	12,350,000
Net asset value per share	$ 38.81	$ 37.49
Market value per share	$ 38.73	$ 37.53
United States Copper Index Fund [Member]
Assets
Cash and cash equivalents	$ 15,373,384	$ 10,753,786
Short-Term Investments	0	295,216
Equity in trading accounts:
Cash and cash equivalents	599,223	1,362,458
Unrealized gain (loss) on open commodity futures contracts	532,625	(903,475)
Receivable from Sponsor (Note 4)	73,218	51,299
Dividends receivable	3,642	1,356
Interest receivable	61	221
Total assets	16,582,153	11,560,861
Liabilities and Capital
Payable due to Broker	14,739	0
Management fees payable (Note 4)	6,541	6,113
Professional fees payable	36,625	49,800
Directors' fees and insurance payable	289	53
Total liabilities	58,194	55,966
Commitments and Contingencies (Notes 4, 5 and 6)
Capital
Sponsor	0	0
Shareholders	16,523,959	11,504,895
Total Capital	16,523,959	11,504,895
Total liabilities and capital	$ 16,582,153	$ 11,560,861
Shares outstanding	900,000	700,000
Net asset value per share	$ 18.36	$ 16.44
Market value per share	$ 18.32	$ 16.44
United States Commodity Index Funds Trust [Member]
Assets
Cash and cash equivalents	$ 419,322,802	$ 438,410,816
Short-Term Investments	0	295,216
Equity in trading accounts:
Cash and cash equivalents	36,551,915	52,214,641
Unrealized gain (loss) on open commodity futures contracts	4,194,744	(15,391,459)
Receivable from Sponsor (Note 4)	73,218	51,299
Dividends receivable	54,147	11,339
Interest receivable	551	4,445
Directors' fees and insurance receivable	15,752	22,319
Total assets	460,213,129	475,618,616
Liabilities and Capital
Payable due to Broker	4,333,965	0
Management fees payable (Note 4)	309,516	373,759
Professional fees payable	429,996	654,096
Brokerage commissions payable	43,305	43,305
Directors' fees and insurance payable	289	53
Total liabilities	5,117,071	1,071,213
Commitments and Contingencies (Notes 4, 5 and 6)
Capital
Sponsor	0	0
Shareholders	455,096,058	474,547,403
Total Capital	455,096,058	474,547,403
Total liabilities and capital	$ 460,213,129	$ 475,618,616
Shares outstanding	12,200,000	13,050,000

Condensed Schedule of Investmen

Condensed Schedule of Investments	Mar. 31, 2019USD ($)Contract
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| Foreign Contracts [Member]
Notional Amount	$ 161,033,386
Number of Contracts \| Contract	2,063
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ 10,477,483
% of Capital	2.39%
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| Foreign Contracts [Member] \| LME Tin Futures LT April 2019 contracts, expiring April 2019 [Member]
Notional Amount	$ 33,478,866
Number of Contracts \| Contract	345
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ 3,517,209
% of Capital	0.80%
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| Foreign Contracts [Member] \| LME Zinc Futures LX May 2019 contracts, expiring May 2019 [Member]
Notional Amount	$ 33,015,122
Number of Contracts \| Contract	537
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ 6,638,971
% of Capital	1.52%
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| Foreign Contracts [Member] \| LME Nickel Futures LN November 2019 contracts, expiring November 2019
Notional Amount	$ 31,441,758
Number of Contracts \| Contract	399
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (41,962)
% of Capital	(0.01%)
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| Foreign Contracts [Member] \| LME Tin Futures LT November 2019 contracts, expiring November 2019
Notional Amount	$ 31,726,430
Number of Contracts \| Contract	298
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ 46,995
% of Capital	0.01%
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| Foreign Contracts [Member] \| ICE Brent Crude Oil Futures CO April 2020 contracts, expiring February 2020 [Member]
Notional Amount	$ 31,371,210
Number of Contracts \| Contract	484
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ 316,270
% of Capital	0.07%
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member]
Notional Amount	$ 316,311,199
Number of Contracts \| Contract	9,122
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (6,167,234)
% of Capital	(1.41%)
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| NYMEX Heating Oil Futures HO June 2019 contracts, expiring May 2019
Notional Amount	$ 31,469,605
Number of Contracts \| Contract	378
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (117,680)
% of Capital	(0.03%)
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| COMEX Gold Futures GC June 2019 contracts, expiring June 2019
Notional Amount	$ 31,790,300
Number of Contracts \| Contract	239
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (756,150)
% of Capital	(0.17%)
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| CME Live Cattle Futures LC June 2019 contracts, expiring June 2019
Notional Amount	$ 31,373,750
Number of Contracts \| Contract	655
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (195,750)
% of Capital	(0.04%)
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| ICE Sugar #11 Futures SB July 2019 contracts, expiring June 2019
Notional Amount	$ 31,305,378
Number of Contracts \| Contract	2,217
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (69,407)
% of Capital	(0.02%)
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| CBOT Wheat Futures W July 2019 contracts, expiring July 2019
Notional Amount	$ 34,742,825
Number of Contracts \| Contract	1,333
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (3,850,550)
% of Capital	(0.88%)
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| CME Lean Hogs Futures LH July 2019 contracts, expiring July 2019
Notional Amount	$ 38,090
Number of Contracts \| Contract	1
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (1,210)
% of Capital	0.00%	[1]
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| CME Lean Hogs Futures LH August 2019 contracts, expiring August 2019
Notional Amount	$ 30,743,420
Number of Contracts \| Contract	797
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (1,079,080)
% of Capital	(0.25%)
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| CME Feeder Cattle Futures FC August 2019 contracts, expiring August 2019
Notional Amount	$ 30,741,500
Number of Contracts \| Contract	405
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ 899,125
% of Capital	0.21%
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| NYMEX RBOB Gasoline Futures RB October 2019 contracts, expiring September 2019
Notional Amount	$ 31,360,304
Number of Contracts \| Contract	446
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ 133,808
% of Capital	0.03%
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| CBOT Corn Futures C December 2019 contracts, expiring December 2019 [Member]
Notional Amount	$ 31,375,337
Number of Contracts \| Contract	1,581
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (960,850)
% of Capital	(0.22%)
United States Commodity Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| NYMEX Natural Gas Futures NG March 2020 contracts, expiring February 2020
Notional Amount	$ 31,370,690
Number of Contracts \| Contract	1,070
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (169,490)
% of Capital	(0.04%)
United States Commodity Index Fund [Member] \| Open Futures Contracts - Short [Member] \| Foreign Contracts [Member]
Notional Amount	$ (43,809,241)	[2]
Number of Contracts \| Contract	446	[2]
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (648,130)	[2]
% of Capital	(0.15%)	[2]
United States Commodity Index Fund [Member] \| Open Futures Contracts - Short [Member] \| Foreign Contracts [Member] \| LME Tin Futures LT April 2019 contracts, expiring April 2019 [Member]
Notional Amount	$ (36,844,065)	[2]
Number of Contracts \| Contract	345	[2]
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (153,680)	[2]
% of Capital	(0.04%)	[2]
United States Commodity Index Fund [Member] \| Open Futures Contracts - Short [Member] \| Foreign Contracts [Member] \| LME Zinc Futures LX May 2019 contracts, expiring May 2019 [Member]
Notional Amount	$ (6,965,176)	[2]
Number of Contracts \| Contract	101	[2]
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ (494,450)	[2]
% of Capital	(0.11%)	[2]
United States Commodity Index Fund [Member] \| Open Futures Contracts [Member]
Notional Amount	$ 433,535,344	[3]
Number of Contracts \| Contract	11,631	[3]
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ 3,662,119	[3]
% of Capital	0.83%	[3]
United States Commodity Index Fund [Member] \| Cash Equivalents [Member]
Market Value	$ 439,767,236
% of Capital	100.23%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member]
Market Value	$ 416,017,236
% of Capital	94.82%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 4/04/2019 [Member]
Principal Amount	$ 16,000,000
Market Value	$ 15,996,817
% of Capital	3.65%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.43%, 4/11/2019 [Member]
Principal Amount	$ 30,000,000
Market Value	$ 29,979,917
% of Capital	6.83%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.36%, 4/18/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,988,926
% of Capital	2.28%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.33%, 4/25/2019 [Member]
Principal Amount	$ 20,000,000
Market Value	$ 19,969,187
% of Capital	4.55%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.46%, 5/02/2019 [Member]
Principal Amount	$ 23,000,000
Market Value	$ 22,951,971
% of Capital	5.23%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 5/09/2019 [Member]
Principal Amount	$ 37,000,000
Market Value	$ 36,905,639
% of Capital	8.41%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.43%, 5/23/2019 [Member]
Principal Amount	$ 40,000,000
Market Value	$ 39,860,756
% of Capital	9.08%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.42%, 5/30/2019 [Member]
Principal Amount	$ 8,000,000
Market Value	$ 7,968,468
% of Capital	1.82%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.51%, 6/06/2019 [Member]
Principal Amount	$ 6,000,000
Market Value	$ 5,972,775
% of Capital	1.36%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 6/13/2019 [Member]
Principal Amount	$ 25,000,000
Market Value	$ 24,878,840
% of Capital	5.67%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 6/20/2019 [Member]
Principal Amount	$ 25,000,000
Market Value	$ 24,867,222
% of Capital	5.67%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.49%, 6/27/2019 [Member]
Principal Amount	$ 25,000,000
Market Value	$ 24,851,375
% of Capital	5.66%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 7/05/2019 [Member]
Principal Amount	$ 12,000,000
Market Value	$ 11,923,525
% of Capital	2.72%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.46%, 7/11/2019 [Member]
Principal Amount	$ 42,000,000
Market Value	$ 41,713,223
% of Capital	9.51%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.42%, 7/18/2019 [Member]
Principal Amount	$ 28,000,000
Market Value	$ 27,798,399
% of Capital	6.34%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 7/25/2019 [Member]
Principal Amount	$ 21,000,000
Market Value	$ 20,838,329
% of Capital	4.75%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.46%, 8/08/2019 [Member]
Principal Amount	$ 25,000,000
Market Value	$ 24,782,312
% of Capital	5.65%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.47%, 8/15/2019 [Member]
Principal Amount	$ 25,000,000
Market Value	$ 24,769,555
% of Capital	5.64%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States - Money Market Funds [Member]
Market Value	$ 23,750,000
% of Capital	5.41%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States - Money Market Funds [Member] \| Fidelity Investments Money Market Funds - Government Portfolio [Member]
Principal Amount	$ 7,200,000
Market Value	$ 7,200,000
% of Capital	1.64%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States - Money Market Funds [Member] \| Goldman Sachs Financial Square Funds - Government Fund - Class FS [Member]
Principal Amount	$ 8,550,000
Market Value	$ 8,550,000
% of Capital	1.95%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States - Money Market Funds [Member] \| Morgan Stanley Institutional Liquidity Funds - Government Portfolio [Member]
Principal Amount	$ 8,000,000
Market Value	$ 8,000,000
% of Capital	1.82%
United States Copper Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member]
Notional Amount	$ 15,925,775	[4]
Number of Contracts \| Contract	224	[4]
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ 532,625	[4]
% of Capital	3.22%	[4]
United States Copper Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| COMEX Copper Futures HG May 2019 contracts expiring May 2019 [Member]
Notional Amount	$ 7,741,162
Number of Contracts \| Contract	112
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ 479,637
% of Capital	2.90%
United States Copper Index Fund [Member] \| Open Futures Contracts – Long [Member] \| United States Contracts [Member] \| COMEX Copper Futures HG July 2019 contracts expiring July 2019 [Member]
Notional Amount	$ 8,184,613
Number of Contracts \| Contract	112
Value/Unrealized Gain (Loss) on Open Commodity Contracts	$ 52,988
% of Capital	0.32%
United States Copper Index Fund [Member] \| Cash Equivalents [Member]
Market Value	$ 15,330,079
% of Capital	92.77%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member]
Market Value	$ 12,575,079
% of Capital	76.10%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.40%, 4/04/2019 [Member]
Principal Amount	$ 500,000
Market Value	$ 499,901
% of Capital	3.03%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.43%, 4/11/2019 [Member]
Principal Amount	$ 500,000
Market Value	$ 499,666
% of Capital	3.02%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 4/18/2019 [Member]
Principal Amount	$ 500,000
Market Value	$ 499,429
% of Capital	3.02%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.36%, 4/25/2019 [Member]
Principal Amount	$ 600,000
Market Value	$ 599,068
% of Capital	3.63%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 5/02/2019 [Member]
Principal Amount	$ 600,000
Market Value	$ 598,765
% of Capital	3.62%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.38%, 5/16/2019 [Member]
Principal Amount	$ 500,000
Market Value	$ 498,715
% of Capital	3.02%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.47%, 5/09/2019 [Member]
Principal Amount	$ 400,000
Market Value	$ 398,817
% of Capital	2.41%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.45%, 5/23/2019 [Member]
Principal Amount	$ 600,000
Market Value	$ 597,899
% of Capital	3.62%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.42%, 5/30/2019 [Member]
Principal Amount	$ 500,000
Market Value	$ 498,029
% of Capital	3.01%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 6/06/2019 [Member]
Principal Amount	$ 500,000
Market Value	$ 497,807
% of Capital	3.01%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 6/13/2019 [Member]
Principal Amount	$ 700,000
Market Value	$ 696,608
% of Capital	4.22%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 6/20/2019 [Member]
Principal Amount	$ 700,000
Market Value	$ 696,229
% of Capital	4.21%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.49%, 6/27/2019 [Member]
Principal Amount	$ 400,000
Market Value	$ 397,622
% of Capital	2.41%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 7/05/2019 [Member]
Principal Amount	$ 500,000
Market Value	$ 496,814
% of Capital	3.01%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.48%, 7/11/2019 [Member]
Principal Amount	$ 350,000
Market Value	$ 347,595
% of Capital	2.10%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.42%, 7/18/2019 [Member]
Principal Amount	$ 250,000
Market Value	$ 248,200
% of Capital	1.50%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 7/25/2019 [Member]
Principal Amount	$ 300,000
Market Value	$ 297,690
% of Capital	1.80%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.46%, 8/08/2019 [Member]
Principal Amount	$ 500,000
Market Value	$ 495,646
% of Capital	3.00%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.54%, 8/15/2019 [Member]
Principal Amount	$ 550,000
Market Value	$ 544,817
% of Capital	3.30%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.42%, 8/22/2019 [Member]
Principal Amount	$ 1,200,000
Market Value	$ 1,188,562
% of Capital	7.19%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.48%, 9/05/2019 [Member]
Principal Amount	$ 300,000
Market Value	$ 296,795
% of Capital	1.80%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.48%, 9/12/2019 [Member]
Principal Amount	$ 500,000
Market Value	$ 494,431
% of Capital	2.99%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.46%, 9/19/2019 [Member]
Principal Amount	$ 500,000
Market Value	$ 494,229
% of Capital	2.99%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 9/26/2019 [Member]
Principal Amount	$ 700,000
Market Value	$ 691,745
% of Capital	4.19%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States - Money Market Funds [Member]
Market Value	$ 2,755,000
% of Capital	16.67%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States - Money Market Funds [Member] \| Goldman Sachs Financial Square Funds - Government Fund - Class FS [Member]
Principal Amount	$ 1,520,000
Market Value	$ 1,520,000
% of Capital	9.20%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States - Money Market Funds [Member] \| Morgan Stanley Institutional Liquidity Funds - Government Portfolio [Member]
Principal Amount	$ 1,235,000
Market Value	$ 1,235,000
% of Capital	7.47%

[1]	Represents less than 0.005%.
[2]	All short contracts are offset by long positions in Futures Contracts and are acquired solely for the purpose of reducing a long position (e.g., due to a redemption or to reflect a rebalancing of the SDCI).
[3]	Collateral amounted to $35,952,692 on open futures contracts.
[4]	Collateral amounted to $599,223 on open futures contracts.

Condensed Schedule of Investm_2

Condensed Schedule of Investments (Parenthetical)	3 Months Ended
Condensed Schedule of Investments (Parenthetical)	Mar. 31, 2019USD ($)
United States Commodity Index Fund [Member]
Debt Instrument, Collateral Amount	$ 35,952,692
Interest rate	0.005%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 4/04/2019 [Member]
Expiration date	4/04/2019
Interest rate	2.41%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.43%, 4/11/2019 [Member]
Expiration date	4/11/2019
Interest rate	2.43%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.36%, 4/18/2019 [Member]
Expiration date	4/18/2019
Interest rate	2.36%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.33%, 4/25/2019 [Member]
Expiration date	4/25/2019
Interest rate	2.33%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.46%, 5/02/2019 [Member]
Expiration date	5/02/2019
Interest rate	2.46%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 5/09/2019 [Member]
Expiration date	5/09/2019
Interest rate	2.44%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.43%, 5/23/2019 [Member]
Expiration date	5/23/2019
Interest rate	2.43%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.42%, 5/30/2019 [Member]
Expiration date	5/30/2019
Interest rate	2.42%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.51%, 6/06/2019 [Member]
Expiration date	6/06/2019
Interest rate	2.51%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 6/13/2019 [Member]
Expiration date	6/13/2019
Interest rate	2.41%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 6/20/2019 [Member]
Expiration date	6/20/2019
Interest rate	2.41%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.49%, 6/27/2019 [Member]
Expiration date	6/27/2019
Interest rate	2.49%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 7/05/2019 [Member]
Expiration date	7/05/2019
Interest rate	2.44%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.46%, 7/11/2019 [Member]
Expiration date	7/11/2019
Interest rate	2.46%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.42%, 7/18/2019 [Member]
Expiration date	7/18/2019
Interest rate	2.42%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 7/25/2019 [Member]
Expiration date	7/25/2019
Interest rate	2.44%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.46%, 8/08/2019 [Member]
Expiration date	8/08/2019
Interest rate	2.46%
United States Commodity Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.47%, 8/15/2019 [Member]
Expiration date	8/15/2019
Interest rate	2.47%
United States Copper Index Fund [Member]
Debt Instrument, Collateral Amount	$ 599,223
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.40%, 4/04/2019 [Member]
Expiration date	4/04/2019
Interest rate	2.40%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.43%, 4/11/2019 [Member]
Expiration date	4/11/2019
Interest rate	2.43%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 4/18/2019 [Member]
Expiration date	4/18/2019
Interest rate	2.44%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.36%, 4/25/2019 [Member]
Expiration date	4/25/2019
Interest rate	2.36%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.38%, 5/16/2019 [Member]
Expiration date	5/02/2019
Interest rate	2.41%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.47%, 5/09/2019 [Member]
Expiration date	5/09/2019
Interest rate	2.47%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.38%, 5/16/2019 [Member]
Expiration date	5/16/2019
Interest rate	2.38%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.45%, 5/23/2019 [Member]
Expiration date	5/23/2019
Interest rate	2.45%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.42%, 5/30/2019 [Member]
Expiration date	5/30/2019
Interest rate	2.42%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 6/06/2019 [Member]
Expiration date	6/06/2019
Interest rate	2.41%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 6/13/2019 [Member]
Expiration date	6/13/2019
Interest rate	2.41%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 6/20/2019 [Member]
Expiration date	6/20/2019
Interest rate	2.44%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.49%, 6/27/2019 [Member]
Expiration date	6/27/2019
Interest rate	2.49%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 7/05/2019 [Member]
Expiration date	7/05/2019
Interest rate	2.44%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.48%, 7/11/2019 [Member]
Expiration date	7/11/2019
Interest rate	2.48%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.42%, 7/18/2019 [Member]
Expiration date	7/18/2019
Interest rate	2.42%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.44%, 7/25/2019 [Member]
Expiration date	7/25/2019
Interest rate	2.44%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.46%, 8/08/2019 [Member]
Expiration date	8/08/2019
Interest rate	2.46%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.54%, 8/15/2019 [Member]
Expiration date	8/15/2019
Interest rate	2.54%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.42%, 8/22/2019 [Member]
Expiration date	8/22/2019
Interest rate	2.42%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.48%, 9/05/2019 [Member]
Expiration date	9/05/2019
Interest rate	2.48%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.48%, 9/12/2019 [Member]
Expiration date	9/12/2019
Interest rate	2.48%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.46%, 9/19/2019 [Member]
Expiration date	9/19/2019
Interest rate	2.46%
United States Copper Index Fund [Member] \| Cash Equivalents [Member] \| United States Treasury Obligations [Member] \| U.S. Treasury Bills 2.41%, 9/26/2019 [Member]
Expiration date	9/26/2019
Interest rate	2.41%

Condensed Statements of Operati

Condensed Statements of Operations - USD ($)		3 Months Ended
Condensed Statements of Operations - USD ($)		Mar. 31, 2019	Mar. 31, 2018
United States Commodity Index Fund [Member]
Gain (loss) on trading of commodity futures contracts:
Realized gain (loss) on closed positions		$ (3,351,005)	$ 4,628,257
Change in unrealized gain (loss) on open positions		18,150,103	(2,082,239)
Dividend income		114,031	0
Interest income	[1]	2,602,041	1,712,166
ETF transaction fees		4,200	5,950
Total income (loss)		17,519,370	4,264,134
Expenses
Management fees (Note 4)		912,419	1,038,924
Professional fees		164,254	164,254
Brokerage commissions		176,921	169,522
Directors' fees and insurance		22,289	18,335
Total expenses		1,275,883	1,391,035
Net income (loss)		$ 16,243,487	$ 2,873,099
Net income (loss) per share (in dollars per share)		$ 1.32	$ 0.24
Net income (loss) per weighted average share (in dollars per share)		$ 1.36	$ 0.23
Weighted average shares outstanding (in shares)		11,936,667	12,357,222
United States Copper Index Fund [Member]
Gain (loss) on trading of commodity futures contracts:
Realized gain (loss) on closed positions		$ (263,113)	$ 362,412
Change in unrealized gain (loss) on open positions		1,436,100	(1,589,363)
Dividend income		7,079	0
Interest income	[1]	59,658	47,066
ETF transaction fees		2,450	1,050
Total income (loss)		1,242,174	(1,178,835)
Expenses
Management fees (Note 4)		18,704	22,329
Professional fees		24,164	10,664
Brokerage commissions		1,509	2,198
Directors' fees and insurance		561	568
Total expenses		44,938	35,759
Expense waiver (Note 4)		(21,918)	(8,269)
Net expenses		23,020	27,490
Net income (loss)		$ 1,219,154	$ (1,206,325)
Net income (loss) per share (in dollars per share)		$ 1.92	$ (1.75)
Net income (loss) per weighted average share (in dollars per share)		$ 1.83	$ (1.75)
Weighted average shares outstanding (in shares)		665,556	691,111
United States Commodity Index Funds Trust [Member]
Gain (loss) on trading of commodity futures contracts:
Realized gain (loss) on closed positions		$ (3,614,118)	$ 4,960,130
Change in unrealized gain (loss) on open positions		19,586,203	(3,660,316)
Realized gain (loss) on foreign currency transactions		0	47
Change in unrealized gain (loss) on foreign currency translations		0	(15)
Dividend income		121,110	0
Interest income	[1]	2,661,699	1,765,173
ETF transaction fees		6,650	7,000
Total income (loss)		18,761,544	3,072,019
Expenses
Management fees (Note 4)		931,123	1,064,078
Professional fees		188,418	185,582
Brokerage commissions		178,430	172,393
Directors' fees and insurance		22,850	19,170
Total expenses		1,320,821	1,441,223
Expense waiver (Note 4)		(21,918)	(19,168)
Net expenses		1,298,903	1,422,055
Net income (loss)		$ 17,462,641	$ 1,649,964

[1]	Interest income does not exceed paid in kind of 5%.

Statements of Changes in Partne

Statements of Changes in Partners' Capital - USD ($)	United States Commodity Index Fund [Member]	United States Copper Index Fund [Member]	United States Commodity Index Funds Trust [Member]	Sponsor [Member]United States Commodity Index Fund [Member]	Sponsor [Member]United States Copper Index Fund [Member]	Sponsor [Member]United States Commodity Index Funds Trust [Member]	Shareholders [Member]United States Commodity Index Fund [Member]	Shareholders [Member]United States Copper Index Fund [Member]	Shareholders [Member]United States Commodity Index Funds Trust [Member]
Net income (loss)	$ 2,873,099	$ (1,206,325)	$ 1,649,964
Net asset value, beginning of period (in dollars per share) at Dec. 31, 2017	$ 42.48	$ 21.05
Net asset value, end of period (in dollars per share) at Mar. 31, 2018	$ 42.72	$ 19.30
Balances, Beginning at Dec. 31, 2018	$ 463,042,508	$ 11,504,895	474,547,403	$ 0	$ 0		$ 463,042,508	$ 11,504,895	$ 474,547,403
Additions		5,451,099	5,451,099		0	$ 0		5,451,099	5,451,099
Redemptions	(40,713,896)	(1,651,189)	(42,365,085)	0	0	0	(40,713,896)	(1,651,189)	(42,365,085)
Net income (loss)	16,243,487	1,219,154	17,462,641	0	0	0	16,243,487	1,219,154	17,462,641
Balances, Ending at Mar. 31, 2019	$ 438,572,099	$ 16,523,959	$ 455,096,058	$ 0	$ 0	$ 0	$ 438,572,099	$ 16,523,959	$ 455,096,058
Shares Outstanding, Beginning at Dec. 31, 2018	12,350,000	700,000	13,050,000	0	0	0	12,350,000	700,000	13,050,000
Additions	0	300,000	300,000	0	0	0	0	300,000	300,000
Redemptions	(1,050,000)	(100,000)	(1,150,000)	0	0	0	(1,050,000)	(100,000)	(1,150,000)
Shares Outstanding, Ending at Mar. 31, 2019	11,300,000	900,000	12,200,000	0	0	0	11,300,000	900,000	12,200,000
Net asset value, beginning of period (in dollars per share) at Dec. 31, 2018	$ 37.49	$ 16.44
Net asset value, end of period (in dollars per share) at Mar. 31, 2019	$ 38.81	$ 18.36

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows - USD ($)	3 Months Ended
Condensed Statements of Cash Flows - USD ($)	Mar. 31, 2019	Mar. 31, 2018
United States Commodity Index Fund [Member]
Cash Flows from Operating Activities:
Net income (loss)	$ 16,243,487	$ 2,873,099
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Increase) decrease in short-term investments	0	35,669,917
Unrealized (gain) loss on open futures contracts	(18,150,103)	2,082,239
(Increase) decrease in dividends receivable	(40,522)	0
(Increase) decrease in interest receivable	3,734	(34,098)
(Increase) decrease in directors' fees and insurance receivable	6,567	0
(Increase) decrease in ETF transaction fees receivable	0	350
Increase (decrease) in payable due to Broker	4,319,226	0
Increase (decrease) in management fees payable	(64,671)	12,052
Increase (decrease) in professional fees payable	(210,925)	(128,912)
Increase (decrease) in directors' fees and insurance payable	0	7,381
Net cash provided by (used in) operating activities	2,106,793	40,482,028
Cash Flows from Financing Activities:
Addition of shares	0	57,599,905
Redemption of shares	(40,713,896)	(4,261,429)
Net cash provided by (used in) financing activities	(40,713,896)	53,338,476
Net Increase (Decrease) in Cash and Cash Equivalents	(38,607,103)	93,820,504
Total Cash, Cash Equivalents and Equity in Trading Accounts, beginning of period	478,509,213	426,097,875
Total Cash, Cash Equivalents and Equity in Trading Accounts, end of period	439,902,110	519,918,379
United States Copper Index Fund [Member]
Cash Flows from Operating Activities:
Net income (loss)	1,219,154	(1,206,325)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Increase) decrease in short-term investments	295,216	395,657
Unrealized (gain) loss on open futures contracts	(1,436,100)	1,589,363
(Increase) decrease in receivable from Sponsor	(21,919)	(8,269)
(Increase) decrease in dividends receivable	(2,286)	0
(Increase) decrease in interest receivable	160	(2,563)
(Increase) decrease in directors' fees and insurance receivable	0	35
Increase (decrease) in payable due to Broker	14,739	(442,429)
Increase (decrease) in management fees payable	428	1,477
Increase (decrease) in professional fees payable	(13,175)	(20,569)
Increase (decrease) in directors' fees and insurance payable	236	337
Net cash provided by (used in) operating activities	56,453	306,714
Cash Flows from Financing Activities:
Addition of shares	5,451,099	4,174,486
Redemption of shares	(1,651,189)	0
Net cash provided by (used in) financing activities	3,799,910	4,174,486
Net Increase (Decrease) in Cash and Cash Equivalents	3,856,363	4,481,200
Total Cash, Cash Equivalents and Equity in Trading Accounts, beginning of period	12,116,244	7,922,175
Total Cash, Cash Equivalents and Equity in Trading Accounts, end of period	15,972,607	12,403,375
United States Commodity Index Funds Trust [Member]
Cash Flows from Operating Activities:
Net income (loss)	17,462,641	1,649,964
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Increase) decrease in short-term investments	295,216	36,164,341
Unrealized (gain) loss on open futures contracts	(19,586,203)	3,660,316
(Increase) decrease in receivable from Sponsor	(21,919)	(19,168)
(Increase) decrease in dividends receivable	(42,808)	0
(Increase) decrease in interest receivable	3,894	(36,907)
(Increase) decrease in directors' fees and insurance receivable	6,567	218
(Increase) decrease in ETF transaction fees receivable	0	350
Increase (decrease) in payable due to Broker	4,333,965	(442,429)
Increase (decrease) in management fees payable	(64,243)	12,235
Increase (decrease) in professional fees payable	(224,100)	(165,362)
Increase (decrease) in directors' fees and insurance payable	236	7,762
Net cash provided by (used in) operating activities	2,163,246	40,831,320
Cash Flows from Financing Activities:
Addition of shares	5,451,099	61,775,391
Redemption of shares	(42,365,085)	(4,261,429)
Net cash provided by (used in) financing activities	(36,913,986)	57,513,962
Net Increase (Decrease) in Cash and Cash Equivalents	(34,750,740)	98,345,282
Total Cash, Cash Equivalents and Equity in Trading Accounts, beginning of period	490,625,457	435,476,532
Total Cash, Cash Equivalents and Equity in Trading Accounts, end of period	$ 455,874,717	$ 533,821,814

Condensed Statements of Cash _2

Condensed Statements of Cash Flows (Parenthetical) - USD ($)	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
United States Commodity Index Fund [Member]
Components of Cash and Cash Equivalents:
Cash and Cash Equivalents	$ 403,949,418	$ 427,657,030	$ 488,134,267
Equity in Trading Accounts:
Cash and Cash Equivalents	35,952,692		31,784,112
Total Cash, Cash Equivalents and Equity in Trading Accounts	439,902,110		519,918,379
United States Copper Index Fund [Member]
Components of Cash and Cash Equivalents:
Cash and Cash Equivalents	15,373,384	10,753,786	10,662,859
Equity in Trading Accounts:
Cash and Cash Equivalents	599,223		1,740,516
Total Cash, Cash Equivalents and Equity in Trading Accounts	15,972,607		12,403,375
United States Commodity Index Funds Trust [Member]
Components of Cash and Cash Equivalents:
Cash and Cash Equivalents	419,322,802	$ 438,410,816	500,187,061
Equity in Trading Accounts:
Cash and Cash Equivalents	36,551,915		33,634,753
Total Cash, Cash Equivalents and Equity in Trading Accounts	$ 455,874,717		$ 533,821,814

ORGANIZATION AND BUSINESS

ORGANIZATION AND BUSINESS	3 Months Ended
ORGANIZATION AND BUSINESS	Mar. 31, 2019
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. A third series of the Trust, the United States Agriculture Index Fund (“USAG”), was liquidated on September 12, 2018, as discussed below. In addition, a fourth series of the Trust, the USCF Canadian Crude Oil Index Fund (“UCCO”), never commenced operations and filed to withdraw from registration on December 19, 2018. USCI and CPER each issue shares (“shares”) that may be purchased and sold on the NYSE Arca, Inc. (“NYSE Arca”), and, until September 6, 2018, USAG issued shares that were purchased and sold on NYSE Arca. USCI, CPER and USAG are collectively referred to herein as the “Trust Series.” The Trust, and each of its series operates pursuant to the Fourth Amended and Restated Declaration of Trust and Trust Agreement dated as of December 15, 2017 (the “Trust Agreement”). United States Commodity Funds LLC (“USCF”) is the sponsor of the Trust and each of its series and is also responsible for the management of the Trust and each of its series. For purposes of the financial statement presentation, unless specified otherwise, all references will be to the Trust Series. On August 7, 2018, the board of directors of USCF determined that USAG could not continue its business and operations in an economically efficient manner due to USAG’s inability to attract sufficient assets, thereby hindering its ability to operate efficiently. On that date, the board of directors of USCF also authorized and approved the closing and liquidation of USAG together with a plan of liquidation for USAG. The Trust filed a current report on Form 8-K dated August 8, 2018 with the U.S. Securities and Exchange Commission (the “SEC”) that included, as an exhibit a press release and the USAG plan of liquidation. USAG also filed a prospectus supplement with the SEC dated August 8, 2018. On September 6, 2018, USAG began the process of liquidating its portfolio. As a of the close of regular trading on the NYSE Arca on September 6, 2018, USAG ceased accepting orders for Creation Baskets and Redemption Baskets from authorized participants. Trading in the shares of USAG on the NYSE Arca was suspended prior to the open of the market on September 7, 2018. On September 7, 2018, the Trust, on behalf of USAG, filed a post-effective amendment to the registration statement with the SEC to terminate the offering of registered and unsold shares of USAG and, thereafter, the NYSE Arca filed a Form 25 to effect the withdrawal of the listings for USAG’s shares. The liquidation date for USAG was September 12, 2018 and the proceeds of the liquidation were sent to all remaining shareholders of USAG on or about September 13, 2018. For U.S. federal income tax purposes, these distributions to shareholders were treated as liquidating distributions and shareholders recognized gain or loss based on the difference between the amount of cash received as part of the liquidating distribution and their adjusted basis in their shares (taking into account all allocations of income, gain, loss, or deduction for the year of liquidation). Items of income, gain, loss, or deduction recognized as a result of the liquidation of USAG’s portfolio were allocated for U.S. federal tax purposes to the shareholders. Any other items of income, gain, loss, or deduction not attributable to the liquidation of USAG’s portfolio were allocated for U.S. federal income tax purposes in accordance with USAG’s general allocation conventions. For further information concerning the U.S. federal income tax consequences of acquiring, holding, and disposing of shares, please review the section titled “U.S. Federal Income Tax Considerations” in the Prospectus. In addition, shareholders who received such a distribution are encouraged to consult their own tax advisors concerning the impact of the liquidation of USAG in light of their own unique circumstances. 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. 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”) and the United States Gasoline Fund, LP (“UGA”), 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 and “UGA” on February 26, 2008, respectively. As a result of the acquisition of the AMEX by NYSE Euronext, each of USO’s, UNG’s, USL’s and UGA’s shares commenced trading on the NYSE Arca on November 25, 2008. USCF is also the general partner of 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 “UNL” on November 18, 2009 and “BNO” on June 2, 2010, respectively. USCF previously served as the general partner for the United States Short Oil Fund, LP (“DNO”) and the United States Diesel-Heating Oil Fund, LP (“UHN”), both of which were liquidated in 2018. In addition, USCF is the sponsor of the USCF Funds Trust, a Delaware statutory trust, and each of its series, the United States 3x Oil Fund (“USOU”) and the United States 3x Short Oil Fund (“USOD”), which commenced operations on July 20, 2017. All funds listed previously, other than UCCO, USAG, DNO and UHN, are referred to collectively herein as the “Related Public Funds.” Effective as of May 1, 2012, each of USCI and CPER 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 and CPER 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. As noted above, as of the filing of this quarterly report on Form 10-Q, USAG is no longer issuing shares. Authorized Participants pay each Trust Series a transaction fee of $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. 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 SEC and, therefore, do not include all information and footnote disclosure required under generally accepted accounting principles in the United States of America (“U.S. GAAP”). 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 ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	Mar. 31, 2019
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 U.S. 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. The Trust financial statements included its respective series of funds financial statements including USCI, CPER, USAG and UCCO through December 31, 2018. For reporting commencing with the March 31, 2019 reporting period, in conjunction with the liquidation of USAG on September 7, 2018 and the withdrawal of UCCO’s registration on December 19, 2018, the USAG and UCCO financial statements have not been included, but are included in the overall Trust financial statements for the applicable reporting periods. 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 income on funds held at the custodian or a futures commission merchant (“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 U.S. 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 2015. 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, 2019 for any Trust Series. Creations and Redemptions Effective as of May 1, 2012, Authorized Participants may purchase Creation Baskets or redeem Redemption Baskets for USCI and CPER 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 two 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 transaction fee of $350 for each order placed to create one or more Creation Baskets or to redeem one or more Redemption Baskets. 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 . Calculation of Per Share 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 that amount by the total number of shares 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 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, 2019, USCF held 5 shares of USCI and 40 shares of CPER. 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. Reclassification Certain amounts in the accompanying condensed financial statements were reclassified to conform to the current presentation. Use of Estimates The preparation of condensed financial statements in conformity with U.S. 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, 2019
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 5 shares of USCI in the open market. In connection with the Second Amended and Restated Trust Agreement dated November 10, 2010, USAG and CPER were designated as additional series of the Trust. A new series of the Trust was designated on June 1, 2016, the USCF Canadian Crude Oil Index Fund (“UCCO”). USCF and the Trustee entered into the Fourth Amended and Restated Declaration of Trust and Trust Agreement effective as of December 15, 2017. Following the designation of USAG and CPER as additional series, USCF made an initial capital contribution of $3,000 to the Trust. On November 10, 2010, the Trust transferred $1,000 to each of 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 September 7, 2018 all Sponsor Shares of USAG were redeemed and USAG discontinued trading and subsequently liquidated and distributed all proceeds to shareholders, as discussed above. In addition, on March 31, 2018, USCF contributed $1,000 to UCCO, which was deemed an initial capital contribution to the series, and has since been redeemed. 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 be 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, as amended, (“Exchange Act”), 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. As discussed above, USAG is no longer issuing shares and its liquidation date was September 12, 2018. 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 NAV to reflect the daily changes in percentage terms of the SummerHaven Dynamic Commodity Index Total Return SM USCI seeks to achieve its investment objective by investing in Futures Contracts and Other Commodity-Related Investments such that daily changes in its per share NAV closely track the daily changes in the price of the SDCI. USCI’s positions in Commodity Interests are rebalanced on a monthly basis in order to track the changing nature of the SDCI. If Futures Contracts relating to a particular commodity remain in the SDCI from one month to the next, such Futures Contracts are rebalanced to the 7.14% target weight. Specifically, on a specified day near the end of each month (the “Selection Date”), it will be determined if a current Benchmark Component Futures Contract will be replaced by a new Futures Contract in either the same or different underlying commodity as a Benchmark Component Futures Contract for the following month, in which case USCI’s investments would have to be changed accordingly. In order that USCI’s trading does not unduly cause extraordinary market movements, and to make it more difficult for third parties to profit by trading based on market movements that could be expected from changes in the Benchmark Component Futures Contracts, USCI’s investments typically are not rebalanced entirely on a single day, but rather typically rebalanced over a period of four days. After fulfilling the margin and collateral requirements with respect to its Commodity Interests, USCF invests the remainder of USCI’s proceeds from the sale of shares in short-term obligations of the United States government (“Treasuries”) or cash equivalents, and/or merely hold such assets in cash (generally in interest-bearing accounts). USCI’s shares began trading on August 10, 2010. As of March 31, 2019, USCI held 1,894 Futures Contracts on the NYMEX, 2,701 Futures Contracts on the ICE Futures, 2,914 Futures Contracts on the CBOT, 1,858 Futures Contracts on the CME, 2,025 Futures Contracts on the LME and 239 Futures Contracts on the COMEX, totaling 11,631 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 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, 2019, CPER held 224 Futures Contracts on the COMEX. Other Defined Terms – Trust Series The SDCI and the SCI are referred to throughout these Notes to Condensed Financial Statements collectively as the “Applicable Index” or “Indices.” Benchmark Component Futures Contracts and Benchmark Component Copper Futures Contracts are referred to throughout these Notes to Condensed Financial Statements collectively as “Applicable Benchmark Component Futures Contracts.” Other Commodity-Related Investments and Other Copper-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. In addition, SummerHaven is registered as an investment adviser under the Investment Advisers Act of 1940 with the SEC. 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, 2019
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 and CPER 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 January 1, 2016, USCF permanently lowered the management fee to 0.80% (80 basis points) per annum of average daily total net assets for USCI and 0.65% (65 basis points) per annum of average daily total net assets for CPER. 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, 2019 and 2018, none of the Trust Series incurred any registration fees or other offering expenses. Independent Directors’ and Officers’ 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. Each Trust Series shares the fees and expenses on a pro rata basis with each other Trust Series and each Related Public Fund, as described above, based on the relative assets of each fund computed on a daily basis. These fees and expenses for the year ending December 31, 2019 are estimated to be a total of $545,250 for the Trust Series and the Related Public Funds. USCI’s portion of such fees and expenses for the year ending December 31, 2019 is estimated to be a total of $98,250 and CPER’s portion of such fees and expenses for the year ending December 31, 2019 is estimated to be a total of $3,600. 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 $410,000 for the year ending December 31, 2019 for USCI and $40,000 for the year ending December 31, 2019 for CPER. Tax reporting costs fluctuate between years due to the number of shareholders during any given year. 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. USCF pays certain expenses normally borne by CPER to the extent that such expenses exceed 0.15% (15 basis points) of CPER’s NAV, on an annualized basis. USCF has no obligation to continue such payments into subsequent periods. For the three months ended March 31, 2019, USCF waived $21,918 of expenses for CPER. 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, 2019
Contractors [Abstract]
Contracts And Agreements	NOTE 5 — CONTRACTS AND AGREEMENTS Marketing Agent Agreement 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 also borne by USCF. Brown Brothers Harriman & Co. Agreements 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.”) and USCF, 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 BBH&Co. transaction fees ranging from $7 to $15 per transaction. Brokerage and Futures Commission Merchant Agreements 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”). In addition, the Trust on behalf of each of USCI and CPER entered into a Futures and Cleared Derivatives Transactions Customer Account Agreement with RBC Capital Markets LLC (“RBC”), in June of 2018. Each of RBC and WFS are referred to as a “Futures Commissions Merchant” or “FCM.” Each of the Trust's FCM agreements require the FCM to provide services to the applicable 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 the applicable Trust Series' account. In accordance with each agreement, the FCM charges the applicable Trust Series commissions of approximately $7 to $8 per round-turn trade, including applicable exchange, clearing 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 Contracts 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 March 31, 2019 For the three months ended March 31, 2018 Total commissions accrued to brokers $ 176,921 $ 169,522 Total commissions as annualized percentage of average total net assets 0.16 % 0.13 % Commissions accrued as a result of rebalancing $ 173,345 $ 164,193 Percentage of commissions accrued as a result of rebalancing 97.98 % 96.86 % Commissions accrued as a result of creation and redemption activity $ 3,576 $ 5,329 Percentage of commissions accrued as a result of creation and redemption activity 2.02 % 3.14 % The increase in total commissions accrued to brokers for the three months ended March 31, 2019, compared to the three months ended March 31, 2018, was due primarily to a higher number of contracts held and traded. CPER For the three months ended March 31, 2019 For the three months ended March 31, 2018 Total commissions accrued to brokers $ 1,509 $ 2,198 Total commissions as annualized percentage of average total net assets 0.05 % 0.06 % Commissions accrued as a result of rebalancing $ 1,286 $ 1,953 Percentage of commissions accrued as a result of rebalancing 85.22 % 88.85 % Commissions accrued as a result of creation and redemption activity $ 223 $ 245 Percentage of commissions accrued as a result of creation and redemption activity 14.78 % 11.15 % The decrease in total commissions accrued to brokers for the three months ended March 31, 2019, compared to the three months ended March 31, 2018, was due primarily to a lower number of contracts held and traded. SummerHaven Agreements USCF is party to an Amended and Restated Advisory Agreement, dated as of May 1, 2018, 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. Prior to May 1, 2018, for USCI, the fee was 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. Prior to May 1, 2018, for CPER, the fee was equal to the percentage fees paid to USCF minus 0.18%, with that result multiplied by 0.5, minus 0.6% to arrive at the actual fee paid. USCF and SummerHaven amended and restated the existing Advisory Agreement effective as of May 1, 2018. As of May 1, 2018, USCF pays SummerHaven an annual fee of $15,000 per each Trust Series as well as an annual fee of 0.06% of the average daily total net assets of each Trust Series. USCF is also party to an Amended and Restated Licensing Agreement, dated as of May 1, 2018, as amended from time to time, with SummerHaven and SHIM, pursuant to which SHIM grants a license to USCF for the use of certain names and marks, including the Applicable Index for each Trust Series in exchange for a fee to be paid by USCF to SHIM. For the year ended December 31, 2018, USCF paid licensing fees to SummerHaven equal to an annual fee of $15,000 per each Trust Series for the, plus an annual fee of 0.06% of the average daily total net assets of each Trust Series. As a result of the amendment and restatement of the Licensing Agreement and Advisory Agreement in May of 2018, the fees required to be paid by USCF to SummerHaven and SHIM in the aggregate have not changed from the aggregate fees paid by USCF under the two agreements prior to the amendment and restatement.

FINANCIAL INSTRUMENTS, OFF-BALA

FINANCIAL INSTRUMENTS, OFF-BALANCE SHEET RISKS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2019
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, options on futures contracts, cleared swaps and OTC 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, options on futures contracts and cleared swaps 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. Cleared swaps are agreements that are eligible to be cleared by a clearinghouse, e.g., ICE Clear Europe, and provide the efficiencies and benefits that centralized clearing on an exchange offers to traders of futures contracts, including credit risk intermediation and the ability to offset positions initiated with different counterparties. The purchase and sale of futures contracts, options on futures contracts and cleared swaps require margin deposits with an FCM. Additional deposits may be necessary for any loss on contract value. The Commodity Exchange Act requires an 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 through March 31, 2019 were exchange-traded. The risks associated with exchange-traded contracts are generally perceived to be less than those associated with OTC swaps since, in OTC swaps, a party must rely solely on the credit of its respective individual counterparties. However, in the future, if each Trust Series were to enter into non-exchange traded contracts (including Exchange for Related Position or EFRP), it would be subject to the credit risk associated with counterparty non-performance. The credit risk from counterparty non-performance associated with such instruments is the net unrealized gain, if any, on the transaction. Currently, each Trust Series has credit risk under its futures contracts since the sole counterparty to all domestic and foreign futures contracts is the clearinghouse for the exchange on which the relevant contracts are traded. In addition, each Trust Series bears the risk of financial failure by the clearing broker. A Trust Series' cash and other property, such as Treasuries, deposited with an FCM are considered commingled with all other customer funds, subject to the FCM’s segregation requirements. In the event of an 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 an 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 investments in Treasuries, cash and/or cash equivalents with the Trust Series' custodian and would not be impacted by the insolvency of an 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, 2019, USCI and CPER held investments in money market funds in the amounts of $23,750,000 and $2,755,000, respectively. As of December 31, 2018, USCI and CPER held investments in money market funds in the amounts of $6,400,000 and $855,000, respectively. Each Trust Series also 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, 2019 and December 31, 2018, USCI held cash deposits and investments in Treasuries in the amounts of $416,152,110 and $472,109,213, respectively, with the custodian and FCMs. As of March 31, 2019 and December 31, 2018, CPER held cash deposits and investments in Treasuries in the amounts of $13,217,607 and $11,556,460, respectively, with the custodian and FCMs. Some or all of these amounts may be subject to loss should the Trust Series' custodian and/or FCMs cease operations. For derivatives, risks arise from changes in the market value of the contracts. Theoretically, each Trust Series is exposed to market risk equal to the value of Futures Contracts purchased and unlimited liability on such contracts sold short. As both a buyer and a seller of options, each Trust Series pays or receives a premium at the outset and then bears the risk of unfavorable changes in the price of the contract underlying the option. The Trust Series' policy is to continuously monitor its exposure to market and counterparty risk through the use of a variety of financial, position and credit exposure reporting controls and procedures. In addition, the Trust Series or USCF have a policy of requiring review of the credit standing of each broker or counterparty with which they conduct business. The financial instruments held by the applicable Trust Series are reported in its condensed statements of financial condition at market or fair value, or at carrying amounts that approximate fair value, because of their highly liquid nature and short-term maturity.

FINANCIAL HIGHLIGHTS

FINANCIAL HIGHLIGHTS	3 Months Ended
FINANCIAL HIGHLIGHTS	Mar. 31, 2019
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, 2019 and 2018 for the shareholders. This information has been derived from information presented in the condensed financial statements. USCI For the three months ended March 31, 2019 (Unaudited) For the three months ended March 31, 2018 (Unaudited) Per Share Operating Performance: Net asset value, beginning of period $ 37.49 $ 42.48 Total income (loss) 1.43 0.35 Total expenses (0.11 ) (0.11 ) Net increase (decrease) in net asset value 1.32 0.24 Net asset value, end of period $ 38.81 $ 42.72 Total Return 3.52 % 0.56 % Ratios to Average Net Assets Total income (loss) 3.79 % 0.81 % Management fees* 0.80 % 0.80 % Total expenses excluding management fees* 0.32 % 0.27 % Expenses waived* — % — % Net expenses excluding management fees* 0.32 % 0.27 % Net income (loss) 3.51 % 0.55 % * Annualized. ** Effective January 1, 2016, USCF permanently lowered the management fee to 0.80% (80 basis points) per annum of average daily total net assets for USCI. CPER For the three months ended March 31, 2019 (Unaudited) For the three months ended March 31, 2018 (Unaudited) Per Share Operating Performance: Net asset value, beginning of period $ 16.44 $ 21.05 Total income (loss) 1.95 (1.71 ) Net expenses (0.03 ) (0.04 ) Net increase (decrease) in net asset value 1.92 (1.75 ) Net asset value, end of period $ 18.36 $ 19.30 Total Return 11.68 % (8.31 )% Ratios to Average Net Assets Total income (loss) 10.64 % (8.46 )% Management fees* 0.65 % 0.65 % Total expenses excluding management fees* 0.91 % 0.39 % Expenses waived* (0.76 )%† (0.24 )%† Net expenses excluding management fees* 0.15 % 0.15 % Net income (loss) 10.45 % (8.66 )% * Annualized. ** Effective January 1, 2016, USCF permanently lowered the management fee to 0.65% (65 basis points) per annum of average daily total net assets for CPER. † USCF paid certain expenses on a discretionary basis typically borne by CPER where expenses exceeded 0.15% (15 basis points) of CPER’s NAV, on an annualized basis. 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 INSTRUM

FAIR VALUE OF FINANCIAL INSTRUMENTS	3 Months Ended
FAIR VALUE OF FINANCIAL INSTRUMENTS	Mar. 31, 2019
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, 2019 using the fair value hierarchy: At March 31, 2019 Total Level I Level II Level III Short-Term Investments $ 439,767,236 $ 439,767,236 $ — $ — Exchange-Traded Futures Contracts Foreign Contracts 9,829,353 9,829,353 — — United States Contracts (6,167,234 ) (6,167,234 ) — — During the three months ended March 31, 2019, there were no transfers between Level I and Level II. The following table summarizes the valuation of USCI’s securities at December 31, 2018 using the fair value hierarchy: At December 31, 2018 Total Level I Level II Level III Short-Term Investments $ 436,426,995 $ 436,426,995 $ — $ — Exchange-Traded Futures Contracts Foreign Contracts (1,866,820 ) (1,866,820 ) — — United States Contracts (12,621,164 ) (12,621,164 ) — — During the year ended December 31, 2018, there were no transfers between Level I and Level II. The following table summarizes the valuation of CPER’s securities at March 31, 2019 using the fair value hierarchy: At March 31, 2019 Total Level I Level II Level III Short-Term Investments $ 15,330,079 $ 15,330,079 $ — $ — Exchange-Traded Futures Contracts United States Contracts 532,625 532,625 — — During the three months ended March 31, 2019, there were no transfers between Level I and Level II. The following table summarizes the valuation of CPER’s securities at December 31, 2018 using the fair value hierarchy: At December 31, 2018 Total Level I Level II Level III Short-Term Investments $ 9,657,426 $ 9,657,426 $ — $ — Exchange-Traded Futures Contracts United States Contracts (903,475 ) (903,475 ) — — During the year ended December 31, 2018, there were no transfers between Level I and Level II. The Trust and each Trust Series have adopted the provisions of Accounting Standards Codification 815 — Derivatives and Hedging, which require presentation of qualitative disclosures about objectives and strategies for using derivatives, quantitative disclosures about fair value amounts and gains and losses on derivatives. Fair Value of Derivative Instruments Held by USCI Derivatives not Accounted for as Hedging Instruments Condensed Statements of Financial Condition Location Fair Value At March 31, 2019 Fair Value At December 31, 2018 Futures - Commodity Contracts Assets $ 3,662,119 $ (14,487,984 ) Fair Value of Derivative Instruments Held by CPER Derivatives not Accounted for as Hedging Instruments Condensed Statements of Financial Condition Location Fair Value At March 31, 2019 Fair Value At December 31, 2018 Futures - Commodity Contracts Assets $ 532,625 $ (903,475 ) The Effect of Derivative Instruments on the Condensed Statements of Operations of USCI For the three months ended March 31, 2019 For the three months ended March 31, 2018 Derivatives not Accounted for as Hedging Instruments Location of Gain (Loss) on Derivatives Recognized in Income Realized Gain (Loss) on Derivatives Recognized in Income Change in Unrealized Gain (Loss) on Derivatives Recognized in Income Realized Gain (Loss) on Derivatives Recognized in Income Change in Unrealized Gain (Loss) on Derivatives Recognized in Income Futures - Commodity Contracts Realized gain (loss) on closed positions $ (3,351,005 ) $ 4,628,257 Change in unrealized gain (loss) on open positions $ 18,150,103 $ (2,082,239 ) The Effect of Derivative Instruments on the Condensed Statements of Operations of CPER For the three months ended March 31, 2019 For the three months ended March 31, 2018 Derivatives not Accounted for as Hedging Instruments Location of Gain (Loss) on Derivatives Recognized in Income Realized Gain (Loss) on Derivatives Recognized in Income Change in Unrealized Gain (Loss) on Derivatives Recognized in Income Realized Gain (Loss) on Derivatives Recognized in Income Change in Unrealized Gain (Loss) on Derivatives Recognized in Income Futures - Commodity Contracts Realized gain (loss) on closed positions $ (263,113 ) $ 362,412 Change in unrealized gain (loss) on open positions $ 1,436,100 $ (1,589,363 )

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	3 Months Ended
SUBSEQUENT EVENTS	Mar. 31, 2019
Subsequent Events [Abstract]
Subsequent Events	N OTE 9 – SUBSEQUENT EVENTS The Trust and each Trust Series have performed an evaluation of subsequent events through the date the condensed financial statements were issued. This evaluation did not result in any subsequent events that necessitated disclosures and/or adjustments.

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	Mar. 31, 2019
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The financial statements have been prepared in conformity with U.S. 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. The Trust financial statements included its respective series of funds financial statements including USCI, CPER, USAG and UCCO through December 31, 2018. For reporting commencing with the March 31, 2019 reporting period, in conjunction with the liquidation of USAG on September 7, 2018 and the withdrawal of UCCO’s registration on December 19, 2018, the USAG and UCCO financial statements have not been included, but are included in the overall Trust financial statements for the applicable reporting periods.
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 income on funds held at the custodian or a futures commission merchant (“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 U.S. 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 2015. 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, 2019 for any Trust Series.
Creations and Redemptions	Creations and Redemptions Effective as of May 1, 2012, Authorized Participants may purchase Creation Baskets or redeem Redemption Baskets for USCI and CPER 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 two 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 transaction fee of $350 for each order placed to create one or more Creation Baskets or to redeem one or more Redemption Baskets.
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 .
Calculation of Per Share NAV	Calculation of Per Share 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 that amount by the total number of shares 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 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, 2019, USCF held 5 shares of USCI and 40 shares of CPER.
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.
Reclassification	Reclassification Certain amounts in the accompanying condensed financial statements were reclassified to conform to the current presentation.
Use of Estimates	Use of Estimates The preparation of condensed financial statements in conformity with U.S. 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, 2019
Contractors [Abstract]
Brokerage Commissions	USCI For the three months ended March 31, 2019 For the three months ended March 31, 2018 Total commissions accrued to brokers $ 176,921 $ 169,522 Total commissions as annualized percentage of average total net assets 0.16 % 0.13 % Commissions accrued as a result of rebalancing $ 173,345 $ 164,193 Percentage of commissions accrued as a result of rebalancing 97.98 % 96.86 % Commissions accrued as a result of creation and redemption activity $ 3,576 $ 5,329 Percentage of commissions accrued as a result of creation and redemption activity 2.02 % 3.14 % The increase in total commissions accrued to brokers for the three months ended March 31, 2019, compared to the three months ended March 31, 2018, was due primarily to a higher number of contracts held and traded. CPER For the three months ended March 31, 2019 For the three months ended March 31, 2018 Total commissions accrued to brokers $ 1,509 $ 2,198 Total commissions as annualized percentage of average total net assets 0.05 % 0.06 % Commissions accrued as a result of rebalancing $ 1,286 $ 1,953 Percentage of commissions accrued as a result of rebalancing 85.22 % 88.85 % Commissions accrued as a result of creation and redemption activity $ 223 $ 245 Percentage of commissions accrued as a result of creation and redemption activity 14.78 % 11.15 % The decrease in total commissions accrued to brokers for the three months ended March 31, 2019, compared to the three months ended March 31, 2018, was due primarily to a lower number of contracts held and traded.

FINANCIAL HIGHLIGHTS (Tables)

FINANCIAL HIGHLIGHTS (Tables)	3 Months Ended
FINANCIAL HIGHLIGHTS (Tables)	Mar. 31, 2019
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, 2019 and 2018 for the shareholders. This information has been derived from information presented in the condensed financial statements. USCI For the three months ended March 31, 2019 (Unaudited) For the three months ended March 31, 2018 (Unaudited) Per Share Operating Performance: Net asset value, beginning of period $ 37.49 $ 42.48 Total income (loss) 1.43 0.35 Total expenses (0.11 ) (0.11 ) Net increase (decrease) in net asset value 1.32 0.24 Net asset value, end of period $ 38.81 $ 42.72 Total Return 3.52 % 0.56 % Ratios to Average Net Assets Total income (loss) 3.79 % 0.81 % Management fees* 0.80 % 0.80 % Total expenses excluding management fees* 0.32 % 0.27 % Expenses waived* — % — % Net expenses excluding management fees* 0.32 % 0.27 % Net income (loss) 3.51 % 0.55 % * Annualized. ** Effective January 1, 2016, USCF permanently lowered the management fee to 0.80% (80 basis points) per annum of average daily total net assets for USCI. CPER For the three months ended March 31, 2019 (Unaudited) For the three months ended March 31, 2018 (Unaudited) Per Share Operating Performance: Net asset value, beginning of period $ 16.44 $ 21.05 Total income (loss) 1.95 (1.71 ) Net expenses (0.03 ) (0.04 ) Net increase (decrease) in net asset value 1.92 (1.75 ) Net asset value, end of period $ 18.36 $ 19.30 Total Return 11.68 % (8.31 )% Ratios to Average Net Assets Total income (loss) 10.64 % (8.46 )% Management fees* 0.65 % 0.65 % Total expenses excluding management fees* 0.91 % 0.39 % Expenses waived* (0.76 )%† (0.24 )%† Net expenses excluding management fees* 0.15 % 0.15 % Net income (loss) 10.45 % (8.66 )% * Annualized. ** Effective January 1, 2016, USCF permanently lowered the management fee to 0.65% (65 basis points) per annum of average daily total net assets for CPER. † USCF paid certain expenses on a discretionary basis typically borne by CPER where expenses exceeded 0.15% (15 basis points) of CPER’s NAV, on an annualized basis. USCF has no obligation to continue such payments into subsequent periods.

FAIR VALUE OF FINANCIAL INSTR_2

FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	3 Months Ended
FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	Mar. 31, 2019
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, 2019 using the fair value hierarchy: At March 31, 2019 Total Level I Level II Level III Short-Term Investments $ 439,767,236 $ 439,767,236 $ — $ — Exchange-Traded Futures Contracts Foreign Contracts 9,829,353 9,829,353 — — United States Contracts (6,167,234 ) (6,167,234 ) — — During the three months ended March 31, 2019, there were no transfers between Level I and Level II. The following table summarizes the valuation of USCI’s securities at December 31, 2018 using the fair value hierarchy: At December 31, 2018 Total Level I Level II Level III Short-Term Investments $ 436,426,995 $ 436,426,995 $ — $ — Exchange-Traded Futures Contracts Foreign Contracts (1,866,820 ) (1,866,820 ) — — United States Contracts (12,621,164 ) (12,621,164 ) — — During the year ended December 31, 2018, there were no transfers between Level I and Level II. The following table summarizes the valuation of CPER’s securities at March 31, 2019 using the fair value hierarchy: At March 31, 2019 Total Level I Level II Level III Short-Term Investments $ 15,330,079 $ 15,330,079 $ — $ — Exchange-Traded Futures Contracts United States Contracts 532,625 532,625 — — During the three months ended March 31, 2019, there were no transfers between Level I and Level II. The following table summarizes the valuation of CPER’s securities at December 31, 2018 using the fair value hierarchy: At December 31, 2018 Total Level I Level II Level III Short-Term Investments $ 9,657,426 $ 9,657,426 $ — $ — Exchange-Traded Futures Contracts United States Contracts (903,475 ) (903,475 ) — —
Fair Value of Derivative Instruments Held by Usci, Cper, Usag and Usmi	Fair Value of Derivative Instruments Held by USCI Derivatives not Accounted for as Hedging Instruments Condensed Statements of Financial Condition Location Fair Value At March 31, 2019 Fair Value At December 31, 2018 Futures - Commodity Contracts Assets $ 3,662,119 $ (14,487,984 ) Fair Value of Derivative Instruments Held by CPER Derivatives not Accounted for as Hedging Instruments Condensed Statements of Financial Condition Location Fair Value At March 31, 2019 Fair Value At December 31, 2018 Futures - Commodity Contracts Assets $ 532,625 $ (903,475 )
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, 2019 For the three months ended March 31, 2018 Derivatives not Accounted for as Hedging Instruments Location of Gain (Loss) on Derivatives Recognized in Income Realized Gain (Loss) on Derivatives Recognized in Income Change in Unrealized Gain (Loss) on Derivatives Recognized in Income Realized Gain (Loss) on Derivatives Recognized in Income Change in Unrealized Gain (Loss) on Derivatives Recognized in Income Futures - Commodity Contracts Realized gain (loss) on closed positions $ (3,351,005 ) $ 4,628,257 Change in unrealized gain (loss) on open positions $ 18,150,103 $ (2,082,239 ) The Effect of Derivative Instruments on the Condensed Statements of Operations of CPER For the three months ended March 31, 2019 For the three months ended March 31, 2018 Derivatives not Accounted for as Hedging Instruments Location of Gain (Loss) on Derivatives Recognized in Income Realized Gain (Loss) on Derivatives Recognized in Income Change in Unrealized Gain (Loss) on Derivatives Recognized in Income Realized Gain (Loss) on Derivatives Recognized in Income Change in Unrealized Gain (Loss) on Derivatives Recognized in Income Futures - Commodity Contracts Realized gain (loss) on closed positions $ (263,113 ) $ 362,412 Change in unrealized gain (loss) on open positions $ 1,436,100 $ (1,589,363 )

ORGANIZATION AND BUSINESS (Addi

ORGANIZATION AND BUSINESS (Additional Information) (Details) - $ / Basket	Mar. 31, 2019	Mar. 31, 2018	Nov. 15, 2011	Nov. 10, 2010	Aug. 10, 2010
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] \| 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 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	1,000	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

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Additional Information) (Details)	3 Months Ended
	Mar. 31, 2019$ / Basketshares	Mar. 31, 2018$ / Basket	Nov. 15, 2011$ / Basket	Nov. 10, 2010$ / Basket	Aug. 10, 2010$ / Basket
Significant Accounting Policies [Line Items]
Cash equivalents maturity period	6 years
Fee paid by Authorized Purchasers for each order placed to create one or more Creation Baskets or to redeem one or more baskets \| $ / Basket					1,000
United States Commodity Index Fund [Member]
Significant Accounting Policies [Line Items]
Weighted average shares outstanding \| shares	5
United States Copper Index Fund [Member]
Significant Accounting Policies [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 \| $ / Basket		1,000	1,000	1,000
Weighted average shares outstanding \| shares	40
Redemption Baskets [Member] \| United States Commodity Index Fund [Member]
Significant Accounting Policies [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 \| $ / Basket	350
Creation Baskets [Member] \| Effective as of May 1, 2012 [Member] \| United States Commodity Index Fund [Member]
Significant Accounting Policies [Line Items]
Weighted average shares outstanding \| shares	50,000

TRUST SERIES (Additional Inform

TRUST SERIES (Additional Information) (Details)

Sep. 14, 2011shares

Sep. 06, 2011

Aug. 10, 2010USD ($)$ / shares$ / Basketshares

Nov. 15, 2011USD ($)$ / shares$ / Basketshares

Sep. 19, 2011shares

Jul. 30, 2010

Dec. 21, 2009USD ($)shares

Mar. 31, 2019USD ($)$ / shares

Dec. 31, 2018USD ($)$ / shares

Mar. 31, 2018$ / shares$ / Basket

Dec. 31, 2017$ / shares

Apr. 13, 2012$ / shares$ / Basket

Nov. 10, 2010USD ($)$ / Basket

Capital Unit [Line Items]

Sponsor capital contribution

$ 1,000

Capital contribution to trust series

$ 1,000

Units acquisition | shares

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

1,000

Partner sponsor units description

On November 10, 2010, the Trust transferred $1,000 to each of 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.

Future Contract Rebalance Target Weightage

7.14%

United States Commodity Index Fund [Member]

Capital Unit [Line Items]

Sponsor capital contribution

$ 0

$ 3,000

Units acquisition | shares

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

50,000,000

Initial offering price per unit NAV | $ / shares

$ 50

$ 38.81

$ 37.49

$ 42.72

$ 42.48

Number of units issued | shares

100,000

Value of unit issued

$ 5,000,000

Number of registered units

100,000

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

Capital Unit [Line Items]

Future contract held

11,631

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

Capital Unit [Line Items]

Future contract held

1,894

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

Capital Unit [Line Items]

Future contract held

2,701

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

Capital Unit [Line Items]

Future contract held

2,914

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

Capital Unit [Line Items]

Future contract held

1,858

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

Capital Unit [Line Items]

Future contract held

2,025

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

Capital Unit [Line Items]

Future contract held

239

United States Agriculture Index Fund [Member]

Capital Unit [Line Items]

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 | $ / shares

$ 25

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

1,000

United States Copper Index Fund [Member]

Capital Unit [Line Items]

Sponsor capital contribution

$ 0

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 | $ / shares

$ 25

$ 18.36

$ 16.44

$ 19.30

$ 21.05

Number of units issued | shares

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 | $ / Basket

1,000

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

Capital Unit [Line Items]

Future contract held

224

FEES PAID BY EACH TRUST SERIE_2

FEES PAID BY EACH TRUST SERIES AND RELATED PARTY TRANSACTIONS (Additional Information) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2019
Fees Paid and Related Party Transactions [Line Items]
Trustee annual fee	$ 3,000
Directors and Officers Liability Insurance [Member] \| Scenario, Forecast [Member]
Fees Paid and Related Party Transactions [Line Items]
Noninterest Expense Directors Fees		$ 545,250
United States Commodity Index Fund [Member]
Fees Paid and Related Party Transactions [Line Items]
Percentage of average daily net assets paid	0.95%
United States Commodity Index Fund [Member] \| Scenario, Forecast [Member]
Fees Paid and Related Party Transactions [Line Items]
Noninterest Expense Directors Fees		98,250
Estimated investor tax reporting cost		410,000
United States Commodity Index Fund [Member] \| Effective January 1, 2016 [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]
Costs and expenses annual limit for reimbursement	0.15%
Expense waiver	$ 21,918
United States Copper Index Fund [Member] \| Scenario, Forecast [Member]
Fees Paid and Related Party Transactions [Line Items]
Noninterest Expense Directors Fees		3,600
Estimated investor tax reporting cost		$ 40,000
United States Agriculture Index Fund [Member] \| Effective January 1, 2016 [Member]
Fees Paid and Related Party Transactions [Line Items]
Percentage of average daily net assets paid	0.65%

CONTRACTS AND AGREEMENTS (Broke

CONTRACTS AND AGREEMENTS (Brokerage Commission) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
United States Commodity Index Fund [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Brokerage commissions	$ 176,921	$ 169,522
Brokerage commissions as a percentage of average daily net assets	0.16%	0.13%
United States Commodity Index Fund [Member] \| Rebalancing Investments Transaction [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Brokerage commissions	$ 173,345	$ 164,193
Brokerage commissions as a percentage of average daily net assets	97.98%	96.86%
United States Commodity Index Fund [Member] \| Creation and Redemption Activity [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Brokerage commissions	$ 3,576	$ 5,329
Brokerage commissions as a percentage of average daily net assets	2.02%	3.14%
United States Copper Index Fund [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Brokerage commissions	$ 1,509	$ 2,198
Brokerage commissions as a percentage of average daily net assets	0.05%	0.06%
United States Copper Index Fund [Member] \| Rebalancing Investments Transaction [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Brokerage commissions	$ 1,286	$ 1,953
Brokerage commissions as a percentage of average daily net assets	85.22%	88.85%
United States Copper Index Fund [Member] \| Creation and Redemption Activity [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Brokerage commissions	$ 223	$ 245
Brokerage commissions as a percentage of average daily net assets	14.78%	11.15%

CONTRACTS AND AGREEMENTS (Addit

CONTRACTS AND AGREEMENTS (Additional Information) (Details)	3 Months Ended
CONTRACTS AND AGREEMENTS (Additional Information) (Details)	Mar. 31, 2019USD ($)$ / Basket
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Annual transfer agency services fee	$ 20,000
Management fee paid to SummerHaven by USCF	plus an annual fee of 0.06% of the average daily total net assets of each Trust Series.
Management fee description	for USCI, the fee was 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. Prior to May 1, 2018, for CPER, the fee was equal to the percentage fees paid to USCF minus 0.18%, with that result multiplied by 0.5, minus 0.6% 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
Maximum [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Transaction fees per transaction \| $ / Basket	15
Commissions per round-turn trade, including applicable exchange and NFA fees for Futures Contracts and options on Futures Contracts \| $ / Basket	8
Minimum [Member]
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items]
Base amount for determining fee percentage	$ 75,000
Transaction fees per transaction \| $ / Basket	7
Commissions per round-turn trade, including applicable exchange and NFA fees for Futures Contracts and options on Futures Contracts \| $ / Basket	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	0.0465%
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	0.035%
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, OFF-BA_2

FINANCIAL INSTRUMENTS, OFF-BALANCE SHEET RISKS AND CONTINGENCIES (Additional Information) (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
United States Commodity Index Fund [Member]
Carrying Amounts and Fair Values of Financial Instruments or Liabilities [Line Items]
Cash deposits and investments in Treasuries	$ 416,152,110	$ 472,109,213
Deposits, Money Market Deposits	23,750,000	6,400,000
United States Copper Index Fund [Member]
Carrying Amounts and Fair Values of Financial Instruments or Liabilities [Line Items]
Cash deposits and investments in Treasuries	13,217,607	11,556,460
Deposits, Money Market Deposits	$ 2,755,000	$ 855,000

FINANCIAL HIGHLIGHTS (Per Unit

FINANCIAL HIGHLIGHTS (Per Unit Performance Data and Other Supplemental Financial Data) (Details) - $ / shares		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
United States Commodity Index Fund [Member]
Per Share Operating Performance:
Net asset value, beginning of period (in dollars per share)		$ 37.49	$ 42.48
Total income (loss)		1.43	0.35
Total expenses		(0.11)	(0.11)
Net increase (decrease) in net asset value		1.32	0.24
Net asset value, end of period (in dollars per share)		$ 38.81	$ 42.72
Total Return		3.52%	0.56%
Ratios to Average Net Assets
Total income (loss)		3.79%	0.81%
Management fees	[1],[2]	0.80%	0.80%
Total expenses excluding management fees	[1]	0.32%	0.27%
Expenses waived	[1],[2]	0.00%	0.00%
Net expenses excluding management fees	[1]	0.32%	0.27%
Net income (loss)		3.51%	0.55%
United States Copper Index Fund [Member]
Per Share Operating Performance:
Net asset value, beginning of period (in dollars per share)		$ 16.44	$ 21.05
Total income (loss)		1.95	(1.71)
Total expenses		(0.03)	(0.04)
Net increase (decrease) in net asset value		1.92	(1.75)
Net asset value, end of period (in dollars per share)		$ 18.36	$ 19.30
Total Return		11.68%	(8.31%)
Ratios to Average Net Assets
Total income (loss)		10.64%	(8.46%)
Management fees	[1],[3]	0.65%	0.65%
Total expenses excluding management fees	[1]	0.91%	0.39%
Expenses waived	[1],[3],[4]	(0.76%)	(0.24%)
Net expenses excluding management fees	[1]	0.15%	0.15%
Net income (loss)		10.45%	(8.66%)

[1]	Annualized
[2]	Effective January 1, 2016, USCF permanently lowered the management fee to 0.80% (80 basis points) per annum of average daily total net assets for USCI.
[3]	Effective January 1, 2016, USCF permanently lowered the management fee to 0.65% (65 basis points) per annum of average daily total net assets for CPER.
[4]	USCF paid certain expenses on a discretionary basis typically borne by CPER where expenses exceeded 0.15% (15 basis points) of CPER’s NAV, on an annualized basis. USCF has no obligation to continue such payments into subsequent periods.

FINANCIAL HIGHLIGHTS (Per Uni_2

FINANCIAL HIGHLIGHTS (Per Unit Performance Data and Other Supplemental Financial Data) (Parenthetical) (Details)		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
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	[1],[2],[3]	0.76%	0.24%
Percentage of Expenses Exceeded		0.15%
United States Copper Index Fund [Member] \| Effective January 1, 2016 [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 Commodity 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],[4]	0.00%	0.00%
United States Commodity Index Fund [Member] \| Effective January 1, 2016 [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 January 1, 2016, USCF permanently lowered the management fee to 0.65% (65 basis points) per annum of average daily total net assets for CPER.
[3]	USCF paid certain expenses on a discretionary basis typically borne by CPER where expenses exceeded 0.15% (15 basis points) of CPER’s NAV, on an annualized basis. USCF has no obligation to continue such payments into subsequent periods.
[4]	Effective January 1, 2016, USCF permanently lowered the management fee to 0.80% (80 basis points) per annum of average daily total net assets for USCI.

FAIR VALUE OF FINANCIAL INSTR_3

FAIR VALUE OF FINANCIAL INSTRUMENTS (Valuation of Securities Using Fair Value Hierarchy) (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
United States Commodity Index Fund [Member] \| Short-Term Investments [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities, fair value	$ 439,767,236	$ 436,426,995
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	9,829,353	(1,866,820)
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	(6,167,234)	(12,621,164)
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	439,767,236	436,426,995
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	9,829,353	(1,866,820)
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	(6,167,234)	(12,621,164)
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	15,330,079	9,657,426
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	532,625	(903,475)
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	15,330,079	9,657,426
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	532,625	(903,475)
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

FAIR VALUE OF FINANCIAL INSTR_4

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, 2019	Dec. 31, 2018
United States Commodity Index Fund [Member]
Derivatives, Fair Value [Line Items]
Derivatives not Accounted for as Hedging Instruments	$ 3,662,119	$ (14,487,984)
United States Copper Index Fund [Member]
Derivatives, Fair Value [Line Items]
Derivatives not Accounted for as Hedging Instruments	$ 532,625	$ (903,475)

FAIR VALUE OF FINANCIAL INSTR_5

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, 2019	Mar. 31, 2018
United States Commodity Index Fund [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized Gain (Loss) on Derivatives Recognized in Income	$ (3,351,005)	$ 4,628,257
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income	18,150,103	(2,082,239)
United States Commodity Index Fund [Member] \| Commodity Contracts [Member] \| Futures [Member] \| Realized gain (loss) on closed positions [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized Gain (Loss) on Derivatives Recognized in Income	(3,351,005)	4,628,257
United States Commodity Index Fund [Member] \| Commodity Contracts [Member] \| Futures [Member] \| Change in unrealized gain (loss) on open positions [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income	18,150,103	(2,082,239)
United States Copper Index Fund [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized Gain (Loss) on Derivatives Recognized in Income	(263,113)	362,412
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income	1,436,100	(1,589,363)
United States Copper Index Fund [Member] \| Commodity Contracts [Member] \| Futures [Member] \| Realized gain (loss) on closed positions [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized Gain (Loss) on Derivatives Recognized in Income	(263,113)	362,412
United States Copper Index Fund [Member] \| Commodity Contracts [Member] \| Futures [Member] \| Change in unrealized gain (loss) on open positions [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income	$ 1,436,100	$ (1,589,363)