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ORGANIZATION AND BUSINESS (Details) |  | 1 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Jan. 04, 2018 $ / shares shares | Feb. 21, 2012 | Apr. 30, 2007 | Apr. 18, 2007 USD ($) $ / shares shares | Dec. 31, 2020 $ / shares $ / item | Dec. 31, 2019 $ / shares | Dec. 31, 2018 $ / shares | [1] | Dec. 31, 2017 $ / shares | [1]
Organization, Consolidation and Presentation of Financial Statements Disclosure |  |  |  |  |  |  |  |
Number of successive valuation days |  |  |  |  | 30 days |  |  |
Average daily percentage change in the price of the Benchmark Futures Contract considered |  |  |  |  | 10.00% |  |  |
Fee paid by Authorized Purchasers for each order placed to create one or more Creation Baskets or to redeem one or more baskets | $ / item |  |  |  |  | 1,000 |  |  |
Number of initially registered units on Form S-1 with the U.S. Securities and Exchange Commission |  |  | 30,000,000 |  |  |  |  |
Net Asset Value Per Unit | $ / shares |  |  |  |  | $ 9.20 | $ 16.91 | $ 24.35 | $ 23.34
Number of units issued | shares |  |  |  | 200,000 |  |  |  |
Value of unit issued | $ |  |  |  | $ 10,001,000 |  |  |  |
Number of registered units |  |  |  |  | 2,280,000,000 |  |  |
Committee For Uniform Securities Identification Procedure Cusip | CUSIP number for UNG’s shares changed to 912318300 |  |  |  |  |  |  |
Prior to Reverse Split [Member] |  |  |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure |  |  |  |  |  |  |  |
Net Asset Value Per Unit | $ / shares | $ 5.69 |  |  | $ 50.00 |  |  |  |
Issued units | shares | 97,466,476 |  |  |  |  |  |  |
Stockholders' Equity, Reverse Stock Split | 1-for-4 reverse share split | 1-for-4 reverse share split |  |  |  |  |  |
Following Reverse Split [Member] |  |  |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure |  |  |  |  |  |  |  |
Net Asset Value Per Unit | $ / shares | $ 22.76 |  |  |  |  |  |  |
Capital Units, Outstanding | shares | 24,366,619 |  |  |  |  |  |  |
Creation Baskets [Member] |  |  |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure |  |  |  |  |  |  |  |
Number of units per basket | $ / item |  |  |  |  | 100,000 |  |  |
Redemption Baskets [Member] |  |  |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure |  |  |  |  |  |  |  |
Number of units per basket | $ / item |  |  |  |  | 100,000 |  |  |
[1] | On January 4, 2018, there was a 1-for-4 reverse share split. Historical shares outstanding, net asset value per share and market value per share have been adjusted for the period shown to reflect the 1-for-4 reverse share split on a retroactive basis.

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- Definition Average daily percentage change in the price of the Benchmark Futures Contract considered for determining the average daily percentage change in the fund's NAV for achieving the entity's investment objective. + References No definition available. + Details
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