Trading Activities - Summary of Gross Fair Values of Derivative Instruments of Futures and Forward Contracts as Separate Assets and Liabilities (Detail) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Derivative [Line Items]
Derivative assets	$ 257,160	$ 240,259
Derivative liabilities	(689,127)	(817,341)
Futures Contracts [Member]
Derivative [Line Items]
Total unrealized appreciation on open futures and forward contracts	795,678	817,717
Total unrealized depreciation on open futures and forward contracts	(574,580)	(580,290)
Net unrealized appreciation on open futures and forward contracts	221,098	237,427
Futures Contracts [Member] \| Commodity [Member]
Derivative [Line Items]
Derivative assets	123,446	352,267
Derivative liabilities	(355,471)	(146,363)
Futures Contracts [Member] \| Equity [Member]
Derivative [Line Items]
Derivative assets	232,420	121,112
Derivative liabilities	(41,912)	(93,411)
Futures Contracts [Member] \| Currencies [Member]
Derivative [Line Items]
Derivative assets	162,158	205,956
Derivative liabilities	(25,595)	(17,590)
Futures Contracts [Member] \| Interest Rates [Member]
Derivative [Line Items]
Derivative assets	277,654	138,382
Derivative liabilities	(151,602)	(322,926)
Forward Contracts [Member]
Derivative [Line Items]
Derivative assets	36,062	2,832
Total unrealized appreciation on open futures and forward contracts	150,609	239,883
Derivative liabilities	(114,547)	(237,051)
Total unrealized depreciation on open futures and forward contracts	(114,547)	(237,051)
Net unrealized appreciation on open futures and forward contracts	36,062	2,832
Forward Contracts [Member] \| Commodity [Member]
Derivative [Line Items]
Derivative assets	16,670	87,839
Total unrealized appreciation on open futures and forward contracts	16,670	87,839
Derivative liabilities	(69,322)	(32,341)
Total unrealized depreciation on open futures and forward contracts	(69,322)	(32,341)
Forward Contracts [Member] \| Currencies [Member]
Derivative [Line Items]
Derivative assets	133,939	152,044
Total unrealized appreciation on open futures and forward contracts	133,939	152,044
Derivative liabilities	(45,225)	(204,710)
Total unrealized depreciation on open futures and forward contracts	$ (45,225)	$ (204,710)

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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