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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Registration Fees and Other Offering Expenses

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FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS (Additional Information) (Detail) - 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	USO iscontractually obligated to pay USCF a fee, which is paid monthly, equal to 0.45%per annum of average daily total net assets.
Ongoing Registration Fees and Other Offering Expenses	$ 81,464	$ 85,913
Fees and expenses	75,556	90,610
Licensing fee incurred	72,917	107,553
Scenario, Forecast [Member]
Fees Paid And Related Party Transactions [Line Items]
Estimated investor tax reporting cost			$ 2,100,000
USO And Related Public Funds [Member] \| Scenario, Forecast [Member]
Fees Paid And Related Party Transactions [Line Items]
Fees and expenses			536,000
USO [Member]
Fees Paid And Related Party Transactions [Line Items]
Ongoing Registration Fees and Other Offering Expenses	81,464	85,913
Licensing fee incurred	$ 72,917	$ 107,553
USO [Member] \| Scenario, Forecast [Member]
Fees Paid And Related Party Transactions [Line Items]
Fees and expenses			$ 326,000
Licensing Agreements [Member]
Fees Paid And Related Party Transactions [Line Items]
Fee percentage	0.015%