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CONTRACTS AND AGREEMENTS (Brokerage Commission) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Commissions accrued to brokers	$ 445,015	$ 419,698
Percentage of commissions accrued	0.41%	0.34%
Rebalancing Investments Transaction [Member]
Commissions accrued to brokers	$ 321,081	$ 331,242
Percentage of commissions accrued	72.15%	78.92%
Creation And Redemption Activity [Member]
Commissions accrued to brokers	$ 123,934	$ 88,456
Percentage of commissions accrued	27.85%	21.08%

X

- Definition

Percentage of Average Daily Net Assets

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No definition available.

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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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