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CONTRACTS AND AGREEMENTS - Brokerage and Futures Commissions Merchant Agreements (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Total commissions accrued to brokers | $ 1,633 | $ 1,231 | $ 1,334
Total commissions as annualized percentage of average total net assets | 0.03% | 0.03% | 0.02%
Rebalancing Investments Transaction [Member] |  |  |
Total commissions accrued to brokers | $ 1,153 | $ 1,084 | $ 823
Total commissions as annualized percentage of average total net assets | 70.61% | 88.06% | 61.69%
Creation And Redemption Activity [Member] |  |  |
Total commissions accrued to brokers | $ 480 | $ 147 | $ 511
Total commissions as annualized percentage of average total net assets | 29.39% | 11.94% | 38.31%

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- Definition Percentage of Average Daily Net Assets + References No definition available. + Details
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- Definition The amount of expense during the period for floor brokerage fees paid to other broker-dealers to execute trades on their behalf, stock exchange fees, order flow fees, and clearance fees. + References No definition available. + Details
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- Details
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Period Type: |

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- Details
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Namespace Prefix: |
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Period Type: |