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FAIR VALUE OF FINANCIAL INSTRUMENTS - Valuation of UNG's securities using the fair value hierarchy (Details) - USD ($) | Mar. 31, 2024 | Dec. 31, 2023
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Short-Term Investments |  |
FAIR VALUE OF FINANCIAL INSTRUMENTS |  |
Fair value of securities | $ 70,950,000 | $ 70,950,000
Exchange-Traded Futures Contracts | United States Contracts |  |
FAIR VALUE OF FINANCIAL INSTRUMENTS |  |
Fair value of securities | (19,516,706) | 40,072,461
Exchange-Traded Futures Contracts | OTC Commodity Swap Contracts |  |
FAIR VALUE OF FINANCIAL INSTRUMENTS |  |
Fair value of securities | (831) | 14,903,211
Level 1 | Short-Term Investments |  |
FAIR VALUE OF FINANCIAL INSTRUMENTS |  |
Fair value of securities | 70,950,000 | 70,950,000
Level 1 | Exchange-Traded Futures Contracts | United States Contracts |  |
FAIR VALUE OF FINANCIAL INSTRUMENTS |  |
Fair value of securities | (19,516,706) | 40,072,461
Level 2 | Exchange-Traded Futures Contracts | OTC Commodity Swap Contracts |  |
FAIR VALUE OF FINANCIAL INSTRUMENTS |  |
Fair value of securities | $ (831) | $ 14,903,211

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- Definition Line items represents the information pertaining to fair value of financial instruments. + References No definition available. + Details
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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