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CONTRACTS AND AGREEMENTS (Brokerage Commissions) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Total commissions accrued to brokers	$ 434	$ 507	$ 1,219	$ 1,604
Total commissions as annualized percentage of average total net assets	0.02%	0.02%	0.02%	0.02%
Rebalancing Investments Transaction [Member]
Total commissions accrued to brokers			$ 909	$ 1,130
Total commissions as annualized percentage of average total net assets	74.57%	70.45%	74.57%	70.45%
Creation And Redemption Activity [Member]
Total commissions accrued to brokers			$ 310	$ 474
Total commissions as annualized percentage of average total net assets	25.43%	29.55%	25.43%	29.55%

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- Definition

Percentage of Average Daily Net Assets

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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.

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No definition available.

+ Details

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- Details

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X

- Details

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