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FAIR VALUE OF FINANCIAL INSTRUMENTS - Valuation of UNG's securities using the fair value hierarchy (Details) - USD ($) | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Short-Term Investments |  |
FAIR VALUE OF FINANCIAL INSTRUMENTS |  |
Fair value of securities | $ 317,800,000 | $ 243,443,000
Exchange-Traded Futures Contracts | United States Contracts |  |
FAIR VALUE OF FINANCIAL INSTRUMENTS |  |
Fair value of securities | (144,765,937) | 1,362,413
Level 1 | Short-Term Investments |  |
FAIR VALUE OF FINANCIAL INSTRUMENTS |  |
Fair value of securities | 317,800,000 | 243,443,000
Level 1 | Exchange-Traded Futures Contracts | United States Contracts |  |
FAIR VALUE OF FINANCIAL INSTRUMENTS |  |
Fair value of securities | $ (144,765,937) | $ 1,362,413

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
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