Trading Activities - Trading Gains and Losses, by Market Sector, on Derivative Instruments (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Total trading results	$ 5,317,468	$ (4,020,509)	$ 2,788,956
Commodity [Member]
Derivative [Line Items]
Total trading results	(2,345,990)	(1,138,112)	(1,213,211)
Equity [Member]
Derivative [Line Items]
Total trading results	3,037,444	(720,406)	11,348,033
Currencies [Member]
Derivative [Line Items]
Total trading results	(564,548)	(482,851)	(4,000,339)
Interest Rates [Member]
Derivative [Line Items]
Total trading results	$ 5,190,562	$ (1,679,140)	$ (3,345,527)