Trading Activities - Summary of Gross Fair Values of Derivative Instruments of Futures and Forward Contracts as Separate Assets and Liabilities (Detail) - USD ($)	Mar. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Derivative assets	$ 382,626
Derivative liabilities	(1,551,207)	$ (1,783,055)
Futures Contracts [Member]
Derivative [Line Items]
Derivative assets	379,307
Total unrealized appreciation on open contracts	566,916	269,890
Derivative liabilities	(187,609)	(460,830)
Total unrealized depreciation on open contracts	(187,609)	(460,829)
Net unrealized appreciation (depreciation) on open contracts	379,307	(190,939)
Futures Contracts [Member] | Commodity [Member]
Derivative [Line Items]
Derivative assets	159,359	175,711
Derivative liabilities	(78,364)	(351,218)
Futures Contracts [Member] | Equity [Member]
Derivative [Line Items]
Derivative assets	102,141	26,772
Derivative liabilities	(64,023)	(40,237)
Futures Contracts [Member] | Interest Rate [Member]
Derivative [Line Items]
Derivative assets	305,416	67,407
Derivative liabilities	(45,222)	(69,374)
Forward Contracts [Member]
Derivative [Line Items]
Derivative assets	3,319
Total unrealized appreciation on open contracts	1,366,917	1,264,408
Derivative liabilities	(1,363,598)	(1,322,225)
Total unrealized depreciation on open contracts	(1,363,598)	(1,322,225)
Net unrealized appreciation (depreciation) on open contracts	3,319	(57,817)
Forward Contracts [Member] | Commodity [Member]
Derivative [Line Items]
Derivative assets	55,289	26,107
Total unrealized appreciation on open contracts	55,289	26,107
Derivative liabilities	(44,741)	(135,773)
Total unrealized depreciation on open contracts	(44,741)	(135,773)
Forward Contracts [Member] | Foreign Currency [Member]
Derivative [Line Items]
Derivative assets	1,311,628	1,238,301
Total unrealized appreciation on open contracts	1,311,628	1,238,301
Derivative liabilities	(1,318,857)	(1,186,452)
Total unrealized depreciation on open contracts	$ (1,318,857)	$ (1,186,452)