Trading Activities - Summary of Gross and Net Amounts Recognized Relating to Assets and Liabilities of Partnership's Derivative Instruments and Transactions Eligible for Offset Subject to Master Netting Agreements or Similar Agreements (Detail) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Gross Amounts Recognized	$ 5,250,485	$ 9,747,286
Gross Amounts Offset in the Statements of Financial Condition	(5,250,485)	(3,930,608)
Net Amounts Presented in the Statements of Financial Condition		5,816,678
Gross Amounts Not Offset in the Statements of Financial Condition, Assets, Financial Instruments	0	0
Gross Amounts Not Offset in the Statements of Financial Condition, Assets, Cash Collateral (Received)/Pledged	0	0
Net Amount, Assets		5,816,678
Gross Amounts Recognized	(6,587,258)	(3,930,608)
Gross Amounts Offset in the Statements of Financial Condition	5,250,485	3,930,608
Net Amounts Presented in the Statements of Financial Condition	(1,336,773)
Gross Amounts Not Offset in the Statements of Financial Condition, Liabilities, Financial Instruments	0	0
Gross Amounts Not Offset in the Statements of Financial Condition, Liabilities, Cash Collateral (Received)/Pledged	0	0
Net Amount, Liabilities	(1,336,773)
Net fair value	(1,336,773)	5,816,678
Futures Contracts [Member]
Derivative [Line Items]
Gross Amounts Recognized	3,370,017	6,470,501
Gross Amounts Offset in the Statements of Financial Condition	(3,370,017)	(1,945,563)
Net Amounts Presented in the Statements of Financial Condition		4,524,938
Gross Amounts Not Offset in the Statements of Financial Condition, Assets, Financial Instruments	0	0
Gross Amounts Not Offset in the Statements of Financial Condition, Assets, Cash Collateral (Received)/Pledged	0	0
Net Amount, Assets		4,524,938
Gross Amounts Recognized	(4,422,974)	(1,945,563)
Gross Amounts Offset in the Statements of Financial Condition	3,370,017	1,945,563
Net Amounts Presented in the Statements of Financial Condition	(1,052,957)
Gross Amounts Not Offset in the Statements of Financial Condition, Liabilities, Financial Instruments	0	0
Gross Amounts Not Offset in the Statements of Financial Condition, Liabilities, Cash Collateral (Received)/Pledged	0	0
Net Amount, Liabilities	(1,052,957)
Forward Contracts [Member]
Derivative [Line Items]
Gross Amounts Recognized	1,880,468	3,276,785
Gross Amounts Offset in the Statements of Financial Condition	(1,880,468)	(1,985,045)
Net Amounts Presented in the Statements of Financial Condition		1,291,740
Gross Amounts Not Offset in the Statements of Financial Condition, Assets, Financial Instruments	0	0
Gross Amounts Not Offset in the Statements of Financial Condition, Assets, Cash Collateral (Received)/Pledged	0	0
Net Amount, Assets		1,291,740
Gross Amounts Recognized	(2,164,284)	(1,985,045)
Gross Amounts Offset in the Statements of Financial Condition	1,880,468	1,985,045
Net Amounts Presented in the Statements of Financial Condition	(283,816)
Gross Amounts Not Offset in the Statements of Financial Condition, Liabilities, Financial Instruments	0	0
Gross Amounts Not Offset in the Statements of Financial Condition, Liabilities, Cash Collateral (Received)/Pledged	0	$ 0
Net Amount, Liabilities	$ (283,816)