Condensed Statements of Cash Flows (USD $)	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Cash Flows from Operating Activities:
Net income	$ 9,156,188	$ 30,392,880
Adjustments to reconcile net income to net cash provided by operating activities:
Decrease in commodity futures trading account - cash and cash equivalents	17,845,169	11,876,572
Unrealized gain on futures contracts	(7,301,720)	(22,692,570)
Increase in dividend receivable	(436)	(590)
Increase in interest receivable	(35)
Increase in other assets	(6,200)	(3,779)
Decrease in investment payable	(33)
Decrease in professional fees payable	(123,586)	(108,485)
Increase in General Partner management fees payable	669	55,212
Increase in brokerage commissions payable		1,980
Increase in other liabilities	6,955	4,829
Net cash provided by operating activities	19,576,971	19,526,049
Cash Flows from Financing Activities:
Addition of partnership units	18,020,754	98,271,913
Redemption of partnership units	(24,885,132)	(18,494,018)
Net cash provided by (used in) financing activities	(6,864,378)	79,777,895
Net Increase in Cash and Cash Equivalents	12,712,593	99,303,944
Cash and Cash Equivalents, beginning of period	123,736,412	152,952,590
Cash and Cash Equivalents, end of period	$ 136,449,005	$ 252,256,534

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).