Trading Activities and Related Risks (Details) (USD $)	6 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Trading Activities and Related Risks
Required margin and good faith deposits with the FCMs and interbank market makers, low end of the range (as a percent)	5.00%
Required margin and good faith deposits with the FCMs and interbank market makers, high end of the range (as a percent)	35.00%
Cash deposited with FCMs and interbank market makers	$ 61,602,299	$ 94,093,764
Cash deposited with FCMs and interbank market makers, as a percentage of net asset value	11.30%	14.80%

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Represents the percentage of net asset value for the amount of cash deposits with broker-dealers.

+ References

No definition available.

+ Details

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- Definition

Represents the high end of the range of percentage of net asset value that is required to maintain as margin and good faith deposits with broker-dealers.

+ References

No definition available.

+ Details

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- Definition

Represents the low end of the range of percentage of net asset value that is required to maintain as margin and good faith deposits with broker-dealers.

+ References

No definition available.

+ Details

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- Definition

The amount due to the entity from other broker-dealers in the form of a deposit paid by the counterparty to demonstrate an intention to complete a purchase (good faith deposit) and also the amount due in the form of collateral deposited by the counterparty to cover the credit risk assumed by the entity (margin deposit).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-BRD

-Paragraph 24

-IssueDate 2006-05-01

-Chapter 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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