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CONTRACTS AND AGREEMENTS (Brokerage Commissions) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Total commissions accrued to brokers	$ 467	$ 663	$ 785	$ 1,097
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			$ 565	$ 623
Total commissions as annualized percentage of average total net assets	71.97%	56.79%	71.97%	56.79%
Creation And Redemption Activity [Member]
Total commissions accrued to brokers			$ 220	$ 474
Total commissions as annualized percentage of average total net assets	28.03%	43.21%	28.03%	43.21%

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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.

+ References

No definition available.

+ Details

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- Details

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X

- Details

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