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CONTRACTS AND AGREEMENTS - Additional Information (Details) $ in Billions | 6 Months Ended
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Jun. 30, 2021 USD ($) $ / item
Maximum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Commissions per round-turn trade, including applicable exchange and NFA fees for Futures Contracts and options on Futures Contracts | $ / item | 8
Minimum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Commissions per round-turn trade, including applicable exchange and NFA fees for Futures Contracts and options on Futures Contracts | $ / item | 7
Marketing Agreement [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Fee percentage | 0.04%
Marketing Agreement [Member] | USNG's assets up to $3 billion [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Fee percentage | 0.06%
Base amount for determining fee percentage | $ | $ 3
Marketing Agreement [Member] | USNG's assets in excess of $3 billion [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Fee percentage | 10.00%
Marketing Agreement [Member] | USNG's assets in excess of $3 billion [Member] | Minimum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Base amount for determining fee percentage | $ | $ 3

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