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CONTRACTS AND AGREEMENTS - Brokerage and Futures Commissions Merchant Agreements (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Total commissions accrued to brokers | $ 1,231 | $ 1,334 | $ 2,209
Total commissions as annualized percentage of average total net assets | 0.03% | 0.02% | 0.02%
Rebalancing Investments Transaction [Member] |  |  |
Total commissions accrued to brokers | $ 1,084 | $ 823 | $ 1,605
Total commissions as annualized percentage of average total net assets | 88.06% | 61.69% | 72.66%
Creation And Redemption Activity [Member] |  |  |
Total commissions accrued to brokers | $ 147 | $ 511 | $ 604
Total commissions as annualized percentage of average total net assets | 11.94% | 38.31% | 27.34%

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- Definition Percentage of Average Daily Net Assets + References No definition available. + Details
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Balance Type: | na
Period Type: | instant

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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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Namespace Prefix: |
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Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |