Trading Activities - Summary of Gross and Net Amounts Recognized Relating to Assets and Liabilities of Partnership's Derivatives (Detail) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Gross Amounts Recognized, Assets	$ 137,302	$ 21,567,614
Gross Amounts Offset in the Statements of Financial Condition, Assets	(108,245)	(15,690,280)
Amounts Presented in the Statements of Financial Condition, Assets	29,057	5,877,334
Financial Instruments, Assets	0	0
Cash Collateral Received/Pledged, Assets	0	0
Net Amount, Assets	29,057	5,877,334
Gross Amounts Recognized, Liabilities	(108,245)	(15,690,280)
Gross Amounts Offset in the Statements of Financial Condition, Liabilities	108,245	15,690,280
Amounts Presented in the Statements of Financial Condition, Liabilities	0	0
Financial Instruments, Liabilities	0	0
Cash Collateral Received/Pledged, Liabilities	0	0
Net Amount, Liabilities	0	0
Net fair value	29,057	5,877,334
Futures Contracts [Member]
Derivative [Line Items]
Gross Amounts Recognized, Assets		9,793,492
Gross Amounts Offset in the Statements of Financial Condition, Assets		(4,789,432)
Amounts Presented in the Statements of Financial Condition, Assets		5,004,060
Financial Instruments, Assets		0
Cash Collateral Received/Pledged, Assets		0
Net Amount, Assets		5,004,060
Gross Amounts Recognized, Liabilities		(4,789,432)
Gross Amounts Offset in the Statements of Financial Condition, Liabilities		4,789,432
Amounts Presented in the Statements of Financial Condition, Liabilities		0
Financial Instruments, Liabilities		0
Cash Collateral Received/Pledged, Liabilities		0
Net Amount, Liabilities		0
Forward Contracts [Member]
Derivative [Line Items]
Gross Amounts Recognized, Assets	137,302	11,774,122
Gross Amounts Offset in the Statements of Financial Condition, Assets	(108,245)	(10,900,848)
Amounts Presented in the Statements of Financial Condition, Assets	29,057	873,274
Financial Instruments, Assets	0	0
Cash Collateral Received/Pledged, Assets	0	0
Net Amount, Assets	29,057	873,274
Gross Amounts Recognized, Liabilities	(108,245)	(10,900,848)
Gross Amounts Offset in the Statements of Financial Condition, Liabilities	108,245	10,900,848
Amounts Presented in the Statements of Financial Condition, Liabilities	0	0
Financial Instruments, Liabilities	0	0
Cash Collateral Received/Pledged, Liabilities	0	0
Net Amount, Liabilities	$ 0	$ 0