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ORGANIZATION AND BUSINESS (Details) |  | 1 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jan. 04, 2018 $ / shares shares | Apr. 30, 2007 | Apr. 18, 2007 USD ($) $ / shares shares | Jun. 30, 2019 $ / shares $ / item | Dec. 31, 2018 $ / shares | Jun. 30, 2018 $ / shares | Jan. 05, 2018 shares | Dec. 31, 2017 $ / shares
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |  |  |  |  |  |  |
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 |  |  |  | $ 19.83 | $ 24.35 | $ 23.71 |  | $ 23.34
Number of units issued |  |  | 200,000 |  |  |  |  |
Value of unit issued | $ |  |  | $ 10,001,000 |  |  |  |  |
Number of registered units |  |  |  | 2,280,000,000 |  |  |  |
Issued units |  |  |  |  |  |  | 912,318,300 |
United States [Member] | NYMEX Natural Gas Futures Contracts [Member] | Open Futures Contracts - Long [Member] |  |  |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |  |  |  |  |  |  |
Number of Contracts |  |  |  | 14,078 |  |  |  |
United States [Member] | ICE Natural Gas Futures LD1 H Contracts [Member] | Open Futures Contracts - Long [Member] |  |  |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |  |  |  |  |  |  |
Number of Contracts |  |  |  | 0 |  |  |  |
Prior to Reverse Split [Member] |  |  |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |  |  |  |  |  |  |
Net Asset Value Per Unit | $ / shares | $ 5.69 |  | $ 50.00 |  |  |  |  |
Issued units | 97,466,476 |  |  |  |  |  |  |
Stockholders' Equity Note, Stock Split, Conversion Ratio | 4 |  |  |  |  |  |  |
Following Reverse Split [Member] |  |  |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |  |  |  |  |  |  |
Net Asset Value Per Unit | $ / shares | $ 22.76 |  |  |  |  |  |  |
Capital Units, Outstanding | 24,366,619 |  |  |  |  |  |  |
Creation Baskets [Member] |  |  |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |  |  |  |  |  |  |
Number of units per basket | $ / item |  |  |  | 100,000 |  |  |  |
Redemption Baskets [Member] |  |  |  |  |  |  |  |
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |  |  |  |  |  |  |
Number of units per basket | $ / item |  |  |  | 100,000 |  |  |  |

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