Derivative Instruments - Derivatives by Line Item in Statement of Operations (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Futures, Forward, and Swap Contracts
Net gain (loss) from futures and forward currency trading
Total realized and changed in unrealized net gain (loss)	$ 1,107,168	$ 795,051	$ (1,111,188)	$ (5,058,881)
Futures Contracts
Net gain (loss) from futures and forward currency trading
Realized	1,054,015	(3,624,312)	(995,761)	(2,024,091)
Change in unrealized	584,189	3,972,712	(555,052)	(1,982,669)
Total realized and changed in unrealized net gain (loss)	1,638,204	348,400	(1,550,813)	(4,006,760)
Forward Contracts
Net gain (loss) from futures and forward currency trading
Realized	262,786	513,204	159,369	(1,134,274)
Change in unrealized	(253,349)	(526,989)	(139,226)	(515,103)
Total realized and changed in unrealized net gain (loss)	9,437	(13,785)	20,143	(1,649,377)
Swap Contracts
Net gain (loss) from futures and forward currency trading
Change in unrealized	(540,473)	460,436	419,482	597,256
Total realized and changed in unrealized net gain (loss)	$ (540,473)	$ 460,436	$ 419,482	$ 597,256

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

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-Publisher FASB
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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