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CONTRACTS AND AGREEMENTS (Brokerage Commissions) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Total commissions accrued to brokers | $ 3,451 | $ 6,117 | $ 3,918
Total commissions as annualized percentage of average total net assets | 0.03% | 0.04% | 0.02%
Rebalancing Investments Transaction [Member] |  |  |
Total commissions accrued to brokers | $ 3,305 | $ 4,698 | $ 2,126
Total commissions as annualized percentage of average total net assets | 95.77% | 76.80% | 54.26%
Creation And Redemption Activity [Member] |  |  |
Total commissions accrued to brokers | $ 146 | $ 1,419 | $ 1,792
Total commissions as annualized percentage of average total net assets | 4.23% | 23.20% | 45.74%

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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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- Details
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