Schedule of Investments (Unaudited) - Futures Contracts - Futures [Member]		9 Months Ended	12 Months Ended
		Sep. 30, 2016 USD ($) Contract	Dec. 31, 2015 USD ($) Contract
Investment Holdings [Line Items]
Percentage of Shareholders' Equity		0.04%	0.80%
Unrealized Appreciation/ (Depreciation)	[1]	$ 317,845	$ 9,076,613
Notional Value		$ 740,187,600	$ 1,133,790,090
United States of America, Dollars | ICE FUTURES U.S. [Member]
Investment Holdings [Line Items]
Percentage of Shareholders' Equity		0.04%	0.80%
Unrealized Appreciation/ (Depreciation)	[1]	$ 317,845	$ 9,076,613
Notional Value		$ 740,187,600	$ 1,133,790,090
Number of Contracts | Contract		7,760	11,482
Maturity Date		Dec. 19, 2016	Mar. 14, 2016

[1] Unrealized appreciation/(depreciation) is presented above, net by contract.