Costs incurred and are directly related to generating license revenue. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark.

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Amount of general expenses not normally included in Other Operating Costs and Expenses.

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Fees Paid and Related Party Transactions [Line Items]

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FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS (Additional Information) (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2018
Fees Paid and Related Party Transactions [Line Items]
USCF Management Fee	USL iscontractually obligated to pay USCF a fee, which is paid monthly, equal to 0.60%per annum of average daily total net assets.
Licensing fee incurred	$ 3,182	$ 4,327
Estimated directors' fees and expenses	$ 3,231	$ 3,120
Scenario, Forecast [Member]
Fees Paid and Related Party Transactions [Line Items]
Estimated investor tax reporting cost			$ 150,000
Estimated directors' fees and expenses			14,400
USL and the Related Public Funds, other than USCI, USAG, CPER and USMI \| Scenario, Forecast [Member]
Fees Paid and Related Party Transactions [Line Items]
Estimated directors' fees and expenses			$ 536,000
Licensing Agreements \| On and after October 20, 2011
Fees Paid and Related Party Transactions [Line Items]
Fee percentage	0.015%