Fair Value Measurements (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Fair Value Measurements
Investments owned - broker trading accounts, fair value		$ 12,395,634
Investments Owned, Fair Value	$ 116,297,654	112,187,759
Recurring basis
Fair Value Measurements
Total	182,678,703	296,637,533
Recurring basis \| U.S. Government securities
Fair Value Measurements
Investments owned - broker trading accounts, fair value		12,395,634
Recurring basis \| Futures Contracts
Fair Value Measurements
Open derivative contracts, fair value	827,595	11,549,467
Recurring basis \| Forward Contracts
Fair Value Measurements
Open derivative contracts, fair value	(240,659)	(181,222)
Recurring basis \| Swap Contracts
Fair Value Measurements
Open derivative contracts, fair value	1,168,100
Recurring basis \| Bank deposits
Fair Value Measurements
Cash and cash equivalents	1,101,389	6,163,896
Recurring basis \| Foreign commercial paper
Fair Value Measurements
Cash and cash equivalents	5,547,926	18,301,948
Investments Owned, Fair Value	4,008,509	2,580,625
Recurring basis \| U.S. commercial paper
Fair Value Measurements
Cash and cash equivalents	57,976,698	136,220,051
Investments Owned, Fair Value	15,173,266	8,106,663
Recurring basis \| U.S. Government-sponsored enterprises
Fair Value Measurements
Investments Owned, Fair Value	82,472,451	89,383,625
Recurring basis \| Foreign corporate bonds
Fair Value Measurements
Investments Owned, Fair Value		1,553,227
Recurring basis \| U.S. corporate bonds
Fair Value Measurements
Investments Owned, Fair Value	14,643,428	10,563,619
Recurring basis \| Level 1
Fair Value Measurements
Total	1,928,984	17,713,363
Recurring basis \| Level 1 \| Futures Contracts
Fair Value Measurements
Open derivative contracts, fair value	827,595	11,549,467
Recurring basis \| Level 1 \| Bank deposits
Fair Value Measurements
Cash and cash equivalents	1,101,389	6,163,896
Recurring basis \| Level 2
Fair Value Measurements
Total	180,749,719	278,924,170
Recurring basis \| Level 2 \| U.S. Government securities
Fair Value Measurements
Investments owned - broker trading accounts, fair value		12,395,634
Recurring basis \| Level 2 \| Forward Contracts
Fair Value Measurements
Open derivative contracts, fair value	(240,659)	(181,222)
Recurring basis \| Level 2 \| Swap Contracts
Fair Value Measurements
Open derivative contracts, fair value	1,168,100
Recurring basis \| Level 2 \| Foreign commercial paper
Fair Value Measurements
Cash and cash equivalents	5,547,926	18,301,948
Investments Owned, Fair Value	4,008,509	2,580,625
Recurring basis \| Level 2 \| U.S. commercial paper
Fair Value Measurements
Cash and cash equivalents	57,976,698	136,220,051
Investments Owned, Fair Value	15,173,266	8,106,663
Recurring basis \| Level 2 \| U.S. Government-sponsored enterprises
Fair Value Measurements
Investments Owned, Fair Value	82,472,451	89,383,625
Recurring basis \| Level 2 \| Foreign corporate bonds
Fair Value Measurements
Investments Owned, Fair Value		1,553,227
Recurring basis \| Level 2 \| U.S. corporate bonds
Fair Value Measurements
Investments Owned, Fair Value	$ 14,643,428	$ 10,563,619

Fair value of the assets less the liabilities of open derivative contracts pledged to counterparties as collateral.

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- Definition

The fair value, as of the balance sheet date, of financial instruments owned by the entity and not pledged to counterparties as collateral. Excludes derivative contracts.

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The fair value, as of the balance sheet date, of financial instruments owned by the entity and pledged to counterparties as collateral. Excludes derivative contracts.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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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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