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CONTRACTS AND AGREEMENTS (Brokerage Commissions) (Details) - USD ($) | 3 Months Ended
--- | ---
Mar. 31, 2019 | Mar. 31, 2018
Total commissions accrued to brokers | $ 372 | $ 318
Total commissions as annualized percentage of average total net assets | 0.03% | 0.02%
Rebalancing Investments Transaction [Member] |  |
Total commissions accrued to brokers | $ 274 | $ 185
Total commissions as annualized percentage of average total net assets | 73.66% | 58.18%
Creation And Redemption Activity [Member] |  |
Total commissions accrued to brokers | $ 98 | $ 133
Total commissions as annualized percentage of average total net assets | 26.34% | 41.82%

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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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Namespace Prefix: |
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Period Type: |

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