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CONTRACTS AND AGREEMENTS (Brokerage Commission) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Commissions accrued to brokers	$ 271,564	$ 445,015
Percentage of commissions accrued	0.38%	0.41%
Rebalancing Investments Transaction [Member]
Commissions accrued to brokers	$ 217,217	$ 321,081
Percentage of commissions accrued	79.99%	72.15%
Creation And Redemption Activity [Member]
Commissions accrued to brokers	$ 54,347	$ 123,934
Percentage of commissions accrued	20.01%	27.85%

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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