Derivative Instruments - Derivatives by Line Item in Statement of Operations (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Futures, Forward, and Swap Contracts
Net gain (loss) from futures and forward currency trading
Total realized and changed in unrealized net gain (loss) from futures and forward currency trading	$ 4,811,259	$ (24,294,720)	$ 17,906,807	$ (7,475,597)
Futures Contracts
Net gain (loss) from futures and forward currency trading
Realized	(13,313)	(17,645,279)	14,597,651	4,090,715
Change in unrealized	5,940,971	(6,370,198)	7,283,395	(10,985,720)
Total realized and changed in unrealized net gain (loss) from futures and forward currency trading	5,927,658	(24,015,477)	21,881,046	(6,895,005)
Forward Contracts
Net gain (loss) from futures and forward currency trading
Realized	(267,066)	(1,034,277)	(383,893)	(1,078,037)
Change in unrealized	643,629	755,034	964,429	497,445
Total realized and changed in unrealized net gain (loss) from futures and forward currency trading	376,563	$ (279,243)	580,536	$ (580,592)
Swap Contracts
Net gain (loss) from futures and forward currency trading
Change in unrealized	(1,492,962)		(4,554,775)
Total realized and changed in unrealized net gain (loss) from futures and forward currency trading	$ (1,492,962)		$ (4,554,775)

Aggregate net gain and losses (whether realized or unrealized) on all derivative instruments held for trading purposes whether or not settled physically.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41322-113958

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4F
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624186-113959

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- Definition

The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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