Trading Activities - Summary of Valuation of Master's Investments (Detail) (USD $)	Jun. 30, 2013	Dec. 31, 2012
Derivative [Line Items]
Net Amounts Presented in the Statement of Financial Condition, Assets	$ 159,521,113	$ 215,122,195
Gross Amounts Recognized, Liabilities	108,396,235	121,642,142
Net unrealized depreciation on open futures and exchange-cleared swaps	(51,124,878)	(93,480,053)
Partnership [Member]
Derivative [Line Items]
Gross Amounts Recognized, Assets	105,926,471	198,277,312
Gross Amounts Offset in the Statement of Financial Condition, Assets	(72,197,039)	(45,393,106)
Net Amounts Presented in the Statement of Financial Condition, Assets	33,729,432	152,884,206
Gross Amounts Recognized, Liabilities	62,731,426	25,737,313
Gross Amount Offset in the Statement of Financial Condition, Liabilities	(45,335,980)	(85,141,466)
Net Amounts Presented in the Statement of Financial Condition, Liabilities	17,395,446	(59,404,153)
Net unrealized depreciation on open futures and exchange-cleared swaps	51,124,878	93,480,053
Futures and Exchange-Cleared Swap Contracts [Member]
Derivative [Line Items]
Net Amounts Presented in the Statement of Financial Condition, Assets	62,232,394	54,683,502
Gross Amounts Recognized, Liabilities	75,408,741	84,404,729
Net unrealized depreciation on open futures and exchange-cleared swaps	13,176,347	29,721,227
Futures and Exchange-Cleared Swap Contracts [Member] | Partnership [Member]
Derivative [Line Items]
Gross Amounts Recognized, Assets	8,115,777	37,825,169
Gross Amounts Offset in the Statement of Financial Condition, Assets	(71,675,064)	(45,379,656)
Net Amounts Presented in the Statement of Financial Condition, Assets	(63,559,287)	(7,554,487)
Gross Amounts Recognized, Liabilities	54,116,616	16,858,333
Gross Amount Offset in the Statement of Financial Condition, Liabilities	(3,733,676)	(39,025,073)
Net Amounts Presented in the Statement of Financial Condition, Liabilities	50,382,940	(22,166,740)
Net unrealized depreciation on open futures and exchange-cleared swaps	(13,176,347)	(29,721,227)
Options Purchased [Member]
Derivative [Line Items]
Net Amounts Presented in the Statement of Financial Condition, Assets	97,288,719	160,438,693
Options Purchased [Member] | Energy [Member]
Derivative [Line Items]
Net Amounts Presented in the Statement of Financial Condition, Assets	97,288,719	160,438,693
Options Purchased [Member] | Partnership [Member]
Derivative [Line Items]
Gross Amounts Recognized, Assets	97,810,694	160,452,143
Gross Amounts Offset in the Statement of Financial Condition, Assets	(521,975)	(13,450)
Net Amounts Presented in the Statement of Financial Condition, Assets	97,288,719	160,438,693
Gross Amounts Recognized, Liabilities	8,614,810	8,878,980
Gross Amount Offset in the Statement of Financial Condition, Liabilities	(41,602,304)	(46,116,393)
Net Amounts Presented in the Statement of Financial Condition, Liabilities	(32,987,494)	(37,237,413)
Options Purchased [Member] | Partnership [Member] | Energy [Member]
Derivative [Line Items]
Net Amounts Presented in the Statement of Financial Condition, Assets	97,288,719	160,438,693
Options Premium Received [Member]
Derivative [Line Items]
Gross Amounts Recognized, Liabilities	32,987,494	37,237,413
Options Premium Received [Member] | Energy [Member]
Derivative [Line Items]
Gross Amounts Recognized, Liabilities	32,987,494	37,237,413
Options Premium Received [Member] | Partnership [Member] | Energy [Member]
Derivative [Line Items]
Gross Amounts Recognized, Liabilities	$ (32,987,494)	$ (37,237,413)