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%