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CONTRACTS AND AGREEMENTS - Additional Information (Details) $ in Billions | 12 Months Ended
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Dec. 31, 2020 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 Oil Futures Contracts and options on Oil 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 Oil Futures Contracts and options on Oil Futures Contracts | $ / item | 7
Marketing Agreement | Maximum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Fee percentage | 10.00%
Marketing Agreement | USL's assets up to $3 billion |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Fee percentage | 0.06%
Marketing Agreement | USL's assets up to $3 billion | Minimum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Base amount for determining fee percentage | $ | $ 3
Marketing Agreement | USL's assets in excess of $3 billion |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Fee percentage | 0.04%
Marketing Agreement | USL's assets in excess of $3 billion | Minimum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Base amount for determining fee percentage | $ | $ 3

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