FAIR VALUE OF FINANCIAL INSTRUMENTS - Fair Value of Derivative Instrument held by Usci, Cper, Usag and Usmi (Details) - Commodity Contracts - Futures - Assets - USD ($)	Sep. 30, 2020	Dec. 31, 2019
United States Commodity Index Fund
FAIR VALUE OF FINANCIAL INSTRUMENTS
Derivatives not Accounted for as Hedging Instruments	$ (5,481,619)	$ (2,138,868)
United States Copper Index Fund
FAIR VALUE OF FINANCIAL INSTRUMENTS
Derivatives not Accounted for as Hedging Instruments	$ (1,610,888)	$ (346,250)

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624163-113959

Name:	us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant