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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Description of the nature of payments to managing member or general partner for management of the day-to-day business functions of the limited liability company (LLC) or limited partnership (LP), including the fee rate, basis of calculation, relevant accounting period, whether the fee is paid to an entity other than the managing member or general partner, or whether the fee is waived.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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- Definition

Noninterest expense related to directors' fees which are fees paid by an Entity to its directors. Directors' fees may be paid in addition to salary and other benefits.

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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

-Paragraph 1

-Subparagraph (SX 210.9-04.14)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.6)

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 6

-Article 5

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- Definition

Base Amount For Fee Percentage

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No definition available.

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Base Fee Percentage

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No definition available.

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Basis Amount for Fee Percentage

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- Definition

Percentage of Average Daily Net Assets

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- Definition

Registration Fees and Other Offering Expenses

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Fees Paid by Fund and Related Party Transactions (Additional Information) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Fees Paid and Related Party Transactions [Line Items]
USCF Management Fee			US12OF is contractually obligated to pay USCF a fee, which is paid monthly, equal to 0.60% per annum of average daily total net assets.
Percentage of average daily total net assets	0.60%		0.60%
Ongoing Registration Fees and Other Offering Expenses	$ 29,687	$ 2,366	$ 59,049	$ 4,732
Licensing fee incurred			7,084	11,577
Estimated investor tax reporting cost			200,000
US12OF and the Related Public Funds [Member]
Fees Paid and Related Party Transactions [Line Items]
Estimated directors' fees and expenses			560,625
Licensing Agreements [Member] \| First $1,000,000,000 of combined net assets of the funds [Member]
Fees Paid and Related Party Transactions [Line Items]
Fee percentage			0.04%
Licensing Agreements [Member] \| First $1,000,000,000 of combined net assets of the funds [Member] \| Maximum [Member]
Fees Paid and Related Party Transactions [Line Items]
Combined assets basis for determining fee percentage	1,000,000,000		1,000,000,000
Licensing Agreements [Member] \| Combined net assets above $1,000,000,000 [Member]
Fees Paid and Related Party Transactions [Line Items]
Fee percentage			0.02%
Licensing Agreements [Member] \| Combined net assets above $1,000,000,000 [Member] \| Minimum [Member]
Fees Paid and Related Party Transactions [Line Items]
Combined assets basis for determining fee percentage	$ 1,000,000,000		$ 1,000,000,000
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