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CONTRACTS AND AGREEMENTS (Brokerage Commission) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Commissions accrued to brokers	$ 1,424,713	$ 1,728,440	$ 2,000,888
Percentage of commissions accrued	0.38%	0.35%	0.37%
Rebalancing Investments Transaction [Member]
Commissions accrued to brokers	$ 1,053,158	$ 1,420,519	$ 1,872,019
Percentage of commissions accrued	73.92%	82.19%	93.56%
Creation And Redemption Activity [Member]
Commissions accrued to brokers	$ 371,555	$ 307,921	$ 128,869
Percentage of commissions accrued	26.08%	17.81%	6.44%

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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.

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- Details

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