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CONTRACTS AND AGREEMENTS (Additional Information) (Details) | 12 Months Ended
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Dec. 31, 2018 USD ($) $ / round-turn
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Annual Fee for transfer agency services | $ 20,000
Maximum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Annual Fee for transfer agency services | 75,000
Transaction fees per transaction | $ 15
Commissions per round-turn trade, including applicable exchange and NFA fees for Oil Futures Contracts and options on Oil Futures Contracts | $ / round-turn | 8
Minimum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Annual Fee for transfer agency services | $ 75,000
Transaction fees per transaction | $ 7
Commissions per round-turn trade, including applicable exchange and NFA fees for Oil Futures Contracts and options on Oil Futures Contracts | $ / round-turn | 7
First $500 million of USL's, USOF's, USNG's, UGA's, USDHO's, USSO's, US12NG's, USBO's, USCI's, CPER's, USAG's and USMI's combined net assets |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Fee percentage | 0.06%
Base amount for determining fee percentage | $ 500,000,000
USL's, USOF's, USNG's, UGA's, USDHO's, USSO's, US12NG's, USBO's, USCI's, CPER's, USAG's and USMI's combined net assets greater than $500 million but less than $1 billion |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Fee percentage | 0.0465%
USL's, USOF's, USNG's, UGA's, USDHO's, USSO's, US12NG's, USBO's, USCI's, CPER's, USAG's and USMI's combined net assets greater than $500 million but less than $1 billion | Maximum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Base amount for determining fee percentage | $ 1,000,000,000
USL's, USOF's, USNG's, UGA's, USDHO's, USSO's, US12NG's, USBO's, USCI's, CPER's, USAG's and USMI's combined net assets greater than $500 million but less than $1 billion | Minimum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Base amount for determining fee percentage | $ 500,000,000
USL's, USOF's, USNG's, UGA's, USDHO's, USSO's, US12NG's, USBO's, USCI's, CPER's, USAG's and USMI's combined net assets exceed $1 billion |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Fee percentage | 0.035%
Base amount for determining fee percentage | $ 1,000,000,000
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 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 | Maximum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Base amount for determining fee percentage | $ 3,000,000,000
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 | $ 3,000,000,000

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