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FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS (Additional Information) (Details) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2018
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |
USCF Management Fee |  |  | USL is contractually 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 | $ 3,010 | $ 4,216 | $ 9,357 | $ 12,528 |
Estimated directors' fees and expenses | $ 3,642 | $ 3,844 | $ 10,456 | $ 10,432 |
Scenario, Forecast [Member] |  |  |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |
Estimated investor tax reporting cost |  |  |  |  | $ 150,000
Estimated directors' fees and expenses |  |  |  |  | 14,500
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 |  |  |  |  | $ 536,200
On and after October 20, 2011 |  |  |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |
Fee percentage |  |  | 0.015% |  |

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- Definition 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://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details
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- Definition Amount of general expenses not normally included in Other Operating Costs and Expenses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.6) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details
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- Definition Base Fee Percentage + References No definition available. + Details
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- Definition Fees Paid and Related Party Transactions [Line Items] + References No definition available. + Details
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- Definition It represent the value of license fees and other offering expenses. + References No definition available. + Details
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