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FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS (Details) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Dec. 31, 2020 USD ($)
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |
Licensing fee incurred | $ 13,789 | $ 11,487 | $ 45,524 | $ 32,617 |
Estimated directors fees and expenses | 19,075 | $ 18,785 | $ 63,273 | 49,368 |
Scenario, Forecast [Member] |  |  |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |
Estimated investor tax reporting cost |  |  |  |  | $ 700,000
USNG and the Related Public Funds [Member] | Scenario, Forecast [Member] |  |  |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |
Estimated directors fees and expenses |  |  |  |  | 574,000
UNITED STATES GAS FUND LP [Member] |  |  |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |
Monthly fee obligated to pay on average daily total net assets, maximum base fee 1,000,000,000 (as a percentage) |  |  | 0.60 |  |
Average daily total net assets | $ 1,000,000,000 |  | $ 1,000,000,000 |  |
Monthly fee obligated to pay on average daily total net assets (as a percentage) |  |  | 0.50 |  |
UNITED STATES GAS FUND LP [Member] | Scenario, Forecast [Member] |  |  |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |
Estimated directors fees and expenses |  |  |  |  | $ 80,000
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 |  |  | $ 281,400 | $ 75,440 |

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