Trading Activities - Offsetting of Derivative Assets and Liabilities (Detail) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Gross Amounts Recognized, Assets	$ 1,086,498	$ 1,683,026
Gross Amounts Offset in the Statements of Financial Condition, Assets	(581,427)	(1,032,826)
Amounts Presented in the Statements of Financial Condition, Assets	505,071	650,200
Net Amount, Assets	505,071	650,200
Gross Amounts Recognized, Liabilities	(645,220)	(1,294,215)
Gross Amounts Offset in the Statements of Financial Condition, Liabilities	581,427	1,032,826
Amounts Presented in the Statements of Financial Condition, Liabilities	(63,793)	(261,389)
Gross Amounts Not Offset in the Statements of Financial Condition, Cash Collateral Received/ Pledged, Liabilities	63,793	261,389
Net fair value	505,071	650,200
Futures Contracts [Member]
Derivative [Line Items]
Gross Amounts Recognized, Assets	761,303	1,455,308
Gross Amounts Offset in the Statements of Financial Condition, Assets	(256,232)	(805,108)
Amounts Presented in the Statements of Financial Condition, Assets	505,071	650,200
Net Amount, Assets	505,071	650,200
Gross Amounts Recognized, Liabilities	(256,232)	(805,108)
Gross Amounts Offset in the Statements of Financial Condition, Liabilities	256,232	805,108
Forward Contracts [Member]
Derivative [Line Items]
Gross Amounts Recognized, Assets	325,195	227,718
Gross Amounts Offset in the Statements of Financial Condition, Assets	(325,195)	(227,718)
Gross Amounts Recognized, Liabilities	(388,988)	(489,107)
Gross Amounts Offset in the Statements of Financial Condition, Liabilities	325,195	227,718
Amounts Presented in the Statements of Financial Condition, Liabilities	(63,793)	(261,389)
Gross Amounts Not Offset in the Statements of Financial Condition, Cash Collateral Received/ Pledged, Liabilities	$ 63,793	$ 261,389