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CONTRACTS AND AGREEMENTS (Additional Information) (Details) | 12 Months Ended
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Dec. 31, 2018 USD ($) $ / Unit
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Annual Fee for custody, fund accounting and fund administration services | $ 20,000
Maximum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Annual Fee for custody, fund accounting and fund administration services | $ 75,000
Transaction fees per transaction | $ / Unit | 15
Commissions per round-turn trade, including applicable exchange and NFA fees for Futures Contracts and options on Futures Contracts | $ / Unit | 8
Minimum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Annual Fee for custody, fund accounting and fund administration services | $ 75,000
Transaction fees per transaction | $ / Unit | 7
Commissions per round-turn trade, including applicable exchange and NFA fees for Futures Contracts and options on Futures Contracts | $ / Unit | 7
First $500 million of USNG's, USOF's, US12OF's, UGA's, USDHO's, USSO's, US12NG's, USBO's, USCI's, CPER's, USAG's and USMI's combined net assets [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Fee percentage | 0.06%
First $500 million of USNG's, USOF's, US12OF's, UGA's, USDHO's, USSO's, US12NG's, USBO's, USCI's, CPER's, USAG's and USMI's combined net assets [Member] | Maximum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Base amount for determining fee percentage | $ 500,000,000
USNG's, USOF's, US12OF'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 [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Fee percentage | 0.0465%
Base amount for determining fee percentage | $ 1,000,000,000
USNG's, USOF's, US12OF'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 [Member] | Maximum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Base amount for determining fee percentage | $ 500,000,000
USNG's, USOF's, US12OF'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 [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Fee percentage | 0.035%
USNG's, USOF's, US12OF'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 [Member] | Maximum [Member] |
Long-Duration Contracts, Assumptions by Product and Guarantee [Line Items] |
Base amount for determining fee percentage | $ 1,000,000,000
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 | $ 3,000,000,000
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 | $ 3,000,000,000

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