Fair Value Measurements (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Fair Value Measurements
Investments Owned, Fair Value	$ 82,280,025	$ 87,511,963
Amount of transfers among Levels 1, 2, and 3	0	0
Recurring basis
Fair Value Measurements
Total - Assets	86,134,214	138,733,348
Recurring basis \| Futures Contracts
Fair Value Measurements
Open derivative contracts, fair value	297,252	2,279,924
Recurring basis \| Forward Contracts
Fair Value Measurements
Open derivative contracts, fair value	(514,397)	705
Recurring basis \| Swap Contracts
Fair Value Measurements
Open derivative contracts, fair value	(137,441)	(734,698)
Recurring basis \| U.S. money market fund
Fair Value Measurements
Cash and cash equivalents	4,208,775	3,965,046
Recurring basis \| Foreign commercial paper
Fair Value Measurements
Cash and cash equivalents		1,328,590
Recurring basis \| U.S. commercial paper
Fair Value Measurements
Cash and cash equivalents		44,381,818
Investments Owned, Fair Value		7,144,238
Recurring basis \| U.S. Government-sponsored enterprises
Fair Value Measurements
Investments Owned, Fair Value	69,173,416	69,209,493
Recurring basis \| U.S. Corporate bonds
Fair Value Measurements
Investments Owned, Fair Value	5,897,469	11,158,232
Recurring basis \| U.S. Mutual Fund
Fair Value Measurements
Investments Owned, Fair Value	7,209,140
Recurring basis \| Level 1
Fair Value Measurements
Total - Assets	4,506,027	6,244,970
Recurring basis \| Level 1 \| Futures Contracts
Fair Value Measurements
Open derivative contracts, fair value	297,252	2,279,924
Recurring basis \| Level 1 \| U.S. money market fund
Fair Value Measurements
Cash and cash equivalents	4,208,775	3,965,046
Recurring basis \| Level 2
Fair Value Measurements
Total - Assets	81,628,187	132,488,378
Recurring basis \| Level 2 \| Forward Contracts
Fair Value Measurements
Open derivative contracts, fair value	(514,397)	705
Recurring basis \| Level 2 \| Swap Contracts
Fair Value Measurements
Open derivative contracts, fair value	(137,441)	(734,698)
Recurring basis \| Level 2 \| Foreign commercial paper
Fair Value Measurements
Cash and cash equivalents		1,328,590
Recurring basis \| Level 2 \| U.S. commercial paper
Fair Value Measurements
Cash and cash equivalents		44,381,818
Investments Owned, Fair Value		7,144,238
Recurring basis \| Level 2 \| U.S. Government-sponsored enterprises
Fair Value Measurements
Investments Owned, Fair Value	69,173,416	69,209,493
Recurring basis \| Level 2 \| U.S. Corporate bonds
Fair Value Measurements
Investments Owned, Fair Value	5,897,469	$ 11,158,232
Recurring basis \| Level 2 \| U.S. Mutual Fund
Fair Value Measurements
Investments Owned, Fair Value	$ 7,209,140

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

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- Definition

Amount of transfers of assets between the levels of the fair value hierarchy.

+ References

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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.

+ References

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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=66048111&loc=d3e19207-110258

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- Definition

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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