FINANCIAL INSTRUMENTS, OFF-BALANCE SHEET RISKS AND CONTINGENCIES - (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
United States Commodity Index Fund
FINANCIAL INSTRUMENTS, OFF-BALANCE SHEET RISKS AND CONTINGENCIES
Deposits, Money Market Deposits	$ 218,101,877	$ 103,316,877
Cash deposits and investments in Treasuries	11,715,351	556,131
United States Copper Index Fund
FINANCIAL INSTRUMENTS, OFF-BALANCE SHEET RISKS AND CONTINGENCIES
Deposits, Money Market Deposits	248,955,787	62,332,787
Cash deposits and investments in Treasuries	$ 15,138,277	$ 778

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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- Definition

Amount of deposits in accounts that offer many of the same services as checking accounts although transactions may be somewhat more limited, share some of the characteristics of a money market fund and are insured by the Federal government, also known as money market accounts.

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- Definition

Carrying Amounts and Fair Values of Financial Instruments or Liabilities [Line Items]

+ References

No definition available.

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