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FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS (Additional Information) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Fees Paid and Related Party Transactions [Line Items] |  |  |
USCF Management Fee | UNG. For these services, UNG is contractually obligated to pay USCF a fee, which is paid monthly, equal to 0.60% per annum of average daily total net assets of $1,000,000,000 or less and 0.50% per annum of average daily total net assets that are greater than $1,000,000,000. |  |
Licensing fee incurred | $ 74,309 | $ 81,594 | $ 91,139
Estimated investor tax reporting cost | 1,000,000 | 400,000 | 800,000
Estimated directors fees and expenses | 64,982 | 94,521 | 118,994
USNG and the Related Public Funds [Member] |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |
Estimated directors fees and expenses | 536,375 | 582,050 | 569,303
UNITED STATES GAS FUND LP [Member] |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |
Licensing fee incurred | 74,309 | 81,594 |
Estimated directors fees and expenses | $ 64,982 |  |
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% |  |
Basis Amount For Fee Percentage | 1,000,000,000 |  |
Combined net assets above $1,000,000,000 [Member] |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |
Fee percentage | 0.02% |  |
Basis Amount For Fee Percentage | 1,000,000,000 |  |
Licensing Agreements [Member] |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |
Fee percentage | 0.015% |  |
United States Oil Fund LP [Member] |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |
Ongoing Registration Fees and Other Offering Expenses | $ 204,998 | 404,792 | 379,106
Estimated directors fees and expenses |  | $ 94,521 | $ 118,994

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- Definition 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. + References 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 210.5-03.2(e)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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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://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 + 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://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 + Details
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