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No definition available.

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-Publisher FASB

-Name Accounting Standards Codification

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

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-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS - (Additional Information) (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2015
Fees Paid and Related Party Transactions [Line Items]
USCF Management Fee			UNL is contractually obligated to pay USCF a fee, which is paid monthly, equal to 0.75% per annum of average daily total net assets.
Estimated directors fees and expenses	$ 746	$ 1,531	$ 1,778	$ 3,311
Licensing fee incurred	672	710	1,321	1,604
Expense waiver (Note 3)	$ 23,928	$ 40,700	$ 41,763	78,745
Licensing Agreements [Member] \| On and after October 20, 2011 [Member]
Fees Paid and Related Party Transactions [Line Items]
Fee percentage			0.015%
Assets basis for determining fee percentage			on all net assets
Future Period - for the year ending December 31, 2014 [Member]
Fees Paid and Related Party Transactions [Line Items]
Estimated investor tax reporting cost			$ 86,000
Future Period - for the year ending December 31, 2014 [Member] \| Maximum [Member]
Fees Paid and Related Party Transactions [Line Items]
Costs and expenses annual limit for reimbursement			0.15%
UNL [Member] \| Subsequent Event [Member]
Fees Paid and Related Party Transactions [Line Items]
Estimated directors fees and expenses					$ 3,000
UNL [Member] \| Related Public Funds [Member] \| Subsequent Event [Member]
Fees Paid and Related Party Transactions [Line Items]
Estimated directors fees and expenses				$ 569,300