v3.25.3

Cover	Oct. 28, 2025
Document Information [Line Items]
Document Type	8-K
Amendment Flag	false
Document Period End Date	Oct. 28, 2025
Entity File Number	001-34833
Entity Registrant Name	UNITED STATES COMMODITY INDEX FUNDS TRUST
Entity Central Index Key	0001479247
Entity Tax Identification Number	27-1537655
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	1850 Mt. Diablo Boulevard
Entity Address, Address Line Two	Suite 640
Entity Address, City or Town	Walnut Creek
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94596
City Area Code	510
Local Phone Number	522-9600
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false
United States Commodity Index Fund [Member]
Document Information [Line Items]
Title of 12(b) Security	Shares of United States Commodity Index Fund
Trading Symbol	USCI
Security Exchange Name	NYSEArca
United States Copper Index Fund [Member]
Document Information [Line Items]
Title of 12(b) Security	Shares of United States Copper Index Fund
Trading Symbol	CPER
Security Exchange Name	NYSEArca

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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Address Line 1 such as Attn, Building Name, Street Name

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Name of the City or Town

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Name of the state or province.

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Local phone number for entity.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

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Trading symbol of an instrument as listed on an exchange.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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United States Commodity Index Funds Trust 8-K