Derivatives Not Designated as Hedging Instruments (Detail) (USD $)	Jun. 30, 2012	Dec. 31, 2011
Derivative [Line Items]
Asset Derivatives Fair Value	$ 266,687	$ 992,885
Liability Derivatives Fair Value	(649,225)	(607,419)
Net Fair Value	(382,538)	385,466
Agriculture
Derivative [Line Items]
Asset Derivatives Fair Value	80,272	10,408
Liability Derivatives Fair Value	(110,998)
Net Fair Value	(30,726)	10,408
Currency
Derivative [Line Items]
Asset Derivatives Fair Value	13,751	527,500
Liability Derivatives Fair Value	(116,128)	(350,799)
Net Fair Value	(102,377)	176,701
Energy
Derivative [Line Items]
Asset Derivatives Fair Value	16,608	225,038
Liability Derivatives Fair Value	(60,345)	(119,410)
Net Fair Value	(43,737)	105,628
Indices
Derivative [Line Items]
Asset Derivatives Fair Value	8,390	17,851
Liability Derivatives Fair Value	(241,103)	(47,027)
Net Fair Value	(232,713)	(29,176)
Interest Rates
Derivative [Line Items]
Asset Derivatives Fair Value	55,791	139,768
Liability Derivatives Fair Value	(68,355)	(10,045)
Net Fair Value	(12,564)	129,723
Metals
Derivative [Line Items]
Asset Derivatives Fair Value	91,875	72,320
Liability Derivatives Fair Value	(52,296)	(80,138)
Net Fair Value	$ 39,579	$ (7,818)