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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) | Dec. 31, 2019 $ / item
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Significant Accounting Policies |
Fee paid by Authorized Purchasers for each order placed to create one or more Creation Baskets or to redeem one or more baskets | 1,000
Redemption Baskets [Member] |
Significant Accounting Policies |
Number of units per basket | 100,000

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- Definition Fee Paid Per Order + References No definition available. + Details
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- Definition Number of unit per basket. + References No definition available. + Details
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Balance Type: | na
Period Type: | instant

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- Definition Significant Accounting Policies [Line Items] + References No definition available. + Details
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Namespace Prefix: | ung_
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Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |