Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open derivatives, commodity, or energy contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

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FAIR VALUE OF FINANCIAL INSTRUMENTS - Effect of Derivative Instruments on Condensed Statements of Operations of Usci, Cper, Usag and Usmi (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
FAIR VALUE OF FINANCIAL INSTRUMENTS
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income			$ 4,607,389	$ 10,692,387
United States Commodity Index Fund
FAIR VALUE OF FINANCIAL INSTRUMENTS
Realized Gain (Loss) on Derivatives Recognized in Income	$ 11,808,620	$ (12,236,395)	(40,973,466)	(27,969,141)
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income			3,342,751	9,989,137
United States Commodity Index Fund \| Commodity Contracts \| Futures \| Realized gain (loss) on closed positions
FAIR VALUE OF FINANCIAL INSTRUMENTS
Realized Gain (Loss) on Derivatives Recognized in Income			(40,973,466)	(27,969,141)
United States Commodity Index Fund \| Commodity Contracts \| Futures \| Change in unrealized gain (loss) on open positions
FAIR VALUE OF FINANCIAL INSTRUMENTS
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income			3,342,751	9,989,137
United States Copper Index Fund
FAIR VALUE OF FINANCIAL INSTRUMENTS
Realized Gain (Loss) on Derivatives Recognized in Income	$ 2,112,187	$ (69,112)	1,391,750	(1,250,775)
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income			1,264,638	703,250
United States Copper Index Fund \| Commodity Contracts \| Futures \| Realized gain (loss) on closed positions
FAIR VALUE OF FINANCIAL INSTRUMENTS
Realized Gain (Loss) on Derivatives Recognized in Income			1,391,750	(1,250,775)
United States Copper Index Fund \| Commodity Contracts \| Futures \| Change in unrealized gain (loss) on open positions
FAIR VALUE OF FINANCIAL INSTRUMENTS
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income			$ 1,264,638	$ 703,250