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CONTRACTS AND AGREEMENTS (Brokerage Commissions) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Long Duration Contracts Assumptions By Product And Guarantee [Line Items]
Brokerage commissions	$ 4,869	$ 5,205	$ 17,285	$ 15,370
Brokerage commissions as a percentage of average daily net assets	0.02%	0.03%	0.02%	0.03%
Rebalancing Investments Transaction [Member]
Long Duration Contracts Assumptions By Product And Guarantee [Line Items]
Brokerage commissions			$ 13,033	$ 9,525
Brokerage commissions as a percentage of average daily net assets	75.40%	61.97%	75.40%	61.97%
Trades Necessitated By Creation And Redemption Activity [Member]
Long Duration Contracts Assumptions By Product And Guarantee [Line Items]
Brokerage commissions			$ 4,252	$ 5,845
Brokerage commissions as a percentage of average daily net assets	24.60%	38.03%	24.60%	38.03%

X

- 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Percentage of Average Daily Net Assets

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