2.4.0.82010 - Disclosure - Nature of Business and Significant Accounting Policies (Policies)truefalsefalse1false falsefalseD2013Q2YTDhttp://www.sec.gov/CIK0000845698duration2013-01-01T00:00:002013-06-30T00:00:001true 1us-gaap_AccountingPoliciesAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Nature of Business and Significant Accounting Policies2false 2us-gaap_ConsolidationPolicyTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-size:10.0pt;font-family:Times New Roman;"> Consolidation: The Partnership is the sole member of each of the Trading Companies. The Trading Companies, in turn, are the only members of GP Cash Management. The Partnership presents consolidated financial statements, which include the accounts of the Trading Companies and GP Cash Management. All material inter-company accounts and transactions are eliminated in consolidation. </div>falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy regarding (1) the principles it follows in consolidating or combining the separate financial statements, including the principles followed in determining the inclusion or exclusion of subsidiaries or other entities in the consolidated or combined financial statements and (2) its treatment of interests (for example, common stock, a partnership interest or other means of exerting influence) in other entities, for example consolidation or use of the equity or cost methods of accounting. The accounting policy may also address the accounting treatment for intercompany accounts and transactions, noncontrolling interest, and the income statement treatment in consolidation for issuances of stock by a subsidiary.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 97-2 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 46R -Paragraph 4 -Subparagraph c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph k -Article 1 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 5, 6, 16-19 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 140 -Paragraph 46 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 46R -Paragraph 4 -Subparagraph d -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02, 03 -Article 3A Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 96-16 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 20 -Subparagraph a(2) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 46R -Paragraph 14, 15 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 11: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790 Reference 12: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -URI http://asc.fasb.org/subtopic&trid=2197480 Reference 13: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=18733093&loc=d3e5614-111684 Reference 14: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.3A-02) -URI http://asc.fasb.org/extlink&oid=6959686&loc=d3e355033-122828 Reference 15: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 2-6 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 16: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 40 -Section 45 -URI http://asc.fasb.org/section&trid=2197723 Reference 17: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -URI http://asc.fasb.org/subtopic&trid=2196966 Reference 18: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 325 -SubTopic 20 -URI http://asc.fasb.org/subtopic&trid=2197087 Reference 19: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=16385135&loc=d3e33801-111570 false0Consolidation3false 2us-gaap_UseOfEstimatesus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-size:10.0pt;font-family:Times New Roman;"> Use of estimates: The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. </div>falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6143-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6132-108592 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6061-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-6 -Paragraph 11, 14 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false0Use of estimates4false 2us-gaap_CashAndCashEquivalentsPolicyTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-size:10.0pt;font-family:Times New Roman;"> Cash and cash equivalents: Cash and cash equivalents may include cash, overnight investments, commercial paper, U.S. treasury bills and short-term investments in interest-bearing demand deposits with banks and cash managers with original maturities of three months or less at the date of acquisition. </div>falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for cash and cash equivalents, including the policy for determining which items are treated as cash equivalents. Other information that may be disclosed includes (1) the nature of any restrictions on the entity's use of its cash and cash equivalents, (2) whether the entity's cash and cash equivalents are insured or expose the entity to credit risk, (3) the classification of any negative balance accounts (overdrafts), and (4) the carrying basis of cash equivalents (for example, at cost) and whether the carrying amount of cash equivalents approximates fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4273-108586 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 305 -SubTopic 10 -URI http://asc.fasb.org/subtopic&trid=2122427 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Financial Reporting Release (FRR) -Number 203 -Paragraph 02-03 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Technical Practice Aid (TPA) -Number 2110 -Paragraph 6 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7, 8, 9, 10 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false0Cash and cash equivalents5false 2us-gaap_InvestmentPolicyTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-size:10.0pt;font-family:Times New Roman;"> Valuation of investments: All investments are used for trading purposes and recorded at their estimated fair value, as described in Note 2. </div>falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for investments in financial assets, including marketable securities (debt and equity securities with readily determinable fair values), investments accounted for under the equity method and cost method, securities borrowed and loaned, and repurchase and resale agreements. For marketable securities, the disclosure may include the entity's accounting treatment for transfers between investment categories and how the fair values for such securities are determined. Also, for all investments, an entity may describe its policy for assessing, recognizing and measuring impairment of the investment.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 7-16 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10, 11 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 325 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6872867&loc=d3e40691-111596 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13433-108611 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27290-111563 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 5 -Section M Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2,12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 7-18 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 11: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 2, 12 -Article 5 false0Valuation of investments6false 2gpff_InvestmentTransactionsInvestmentIncomeAndExpensesPolicyTextBlockgpff_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-size:10.0pt;font-family:Times New Roman;"> Investment transactions, investment income and expenses: Futures contracts, forward contracts and options on futures and forward contracts are recorded on a trade date basis and realized gains or losses are recognized when contracts/positions are liquidated. Unrealized gains or losses on open contracts/positions (the difference between contract trade price and market price) or securities are reported in the consolidated statement of financial condition as a net unrealized gain or loss, as there exists a right of offset of unrealized gains or losses in accordance with FASB ASC 210-20, Balance Sheet, Offsetting. Any change in net unrealized gain or loss from the preceding period is reported in the consolidated statement of operations. Interest income and expense is recognized under the accrual basis.   Set forth in Note 10 are instruments and transactions eligible for offset in the consolidated statement of financial condition and which are subject to derivative clearing agreements with the Partnership’s clearing brokers.  Each clearing broker nets margin held on behalf of the Partnership or payment obligations of the clearing broker to the Partnership against any payment obligations of the Partnership to the clearing broker.  The Partnership is required to deposit margin at each clearing broker to meet the original and maintenance requirements established by that clearing broker, and/or the exchange or clearinghouse associated with the exchange on which the instrument is traded.  The derivative clearing agreements give each clearing broker a security interest in this margin to secure any liabilities owed to the clearing broker arising from a default by the Partnership. </div>falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for investment transactions, investment income and expenses.No definition available.false0Investment transactions, investment income and expenses7false 2us-gaap_CommissionsPolicyus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-size:10.0pt;font-family:Times New Roman;"> Commissions: Commissions and other trading fees are reflected separately in the consolidated statement of operations. </div>falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for fees earned by the broker dealer, acting as an agent in the buying and selling of securities and administrative efforts on behalf of customers and may include the timing of commission revenue recognition and presentation in the financial statements. Commissions earned are usually related to the broker dealer's customers' trading volume and the dollar amounts of the trades.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 20 -Section 25 -URI http://asc.fasb.org/section&trid=2176260 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Paragraph 52, 53 -IssueDate 2006-05-01 -Chapter 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false0Commissions8false 2gpff_RedemptionsPayablePolicyTextBlockgpff_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-size:10.0pt;font-family:Times New Roman;"> Redemptions payable: Pursuant to the provisions of FASB ASC 480, Distinguishing Liabilities from Equity, redemptions approved by the General Partner prior to month end with a fixed effective date and fixed amount are recorded as redemptions payable as of month end. </div>falsefalsefalsenonnum:textBlockItemTypenaDescribes an entity's accounting policy for payables for partners' capital withdrawals.No definition available.false0Redemptions payable9false 2us-gaap_IncomeTaxPolicyTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-size:10.0pt;font-family:Times New Roman;"> Income taxes: No provision for income taxes has been made in these consolidated financial statements as each partner is individually responsible for reporting income or loss based on its respective share of the Partnership’s income and expenses as reported for income tax purposes.   The Partnership follows the provisions of ASC 740, Income Taxes. FASB guidance requires the evaluation of tax positions taken or expected to be taken in the course of preparing the Partnership’s tax returns to determine whether the tax positions are  more-likely-than-not” of being sustained “when challenged” or “when examined” by the applicable tax authority. Tax positions not deemed to meet the more-likely-than-not threshold would be recorded as a tax benefit or expense and liability in the current year. As of June 30, 2013, management has determined that there are no material uncertain income tax positions and, accordingly, has not recorded a liability. The Partnership is generally not subject to examination by U.S. federal or state taxing authorities for tax years before 2009. </div>falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 4 -Paragraph 11 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 48 -Paragraph 20 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 25 -URI http://asc.fasb.org/extlink&oid=21917399&loc=d3e32247-109318 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32840-109319 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 30 -URI http://asc.fasb.org/subtopic&trid=2144749 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 954 -SubTopic 740 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6491622&loc=d3e9504-115650 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -URI http://asc.fasb.org/subtopic&trid=2144681 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 17 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32809-109319 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=21917399&loc=d3e32280-109318 Reference 11: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 6-34, 43, 47, 49 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false0Income taxes10false 2gpff_OrganizationAndPublicOfferingCostsPolicyTextBlockgpff_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-size:10.0pt;font-family:Times New Roman;"> Organization and offering costs: All expenses incurred in connection with the organization and the ongoing public offering of partnership interests are paid by the General Partner and are reimbursed to the General Partner by the Partnership. This reimbursement is made monthly. In its discretion, the General Partner may require the Partnership to reimburse the General Partner in any subsequent calendar year for amounts that exceed the limits in Note 5 in any calendar year, provided that the maximum amount reimbursed by the Partnership will not exceed the overall limit. Amounts reimbursed by the Partnership with respect to ongoing public offering expenses are charged to expense from operations at the time of reimbursement or accrual. Any amounts reimbursed by the Partnership with respect to organizational expenses are expensed at the time the reimbursement is incurred or accrued. If the Partnership terminates prior to completion of payment of the calculated amounts to the General Partner, the General Partner will not be entitled to any additional payments, and the Partnership will have no further obligation to the General Partner. At June 30, 2013 and December 31, 2012, all organization and offering costs incurred by the General Partner have been reimbursed. </div>falsefalsefalsenonnum:textBlockItemTypenaDescribes an entity's accounting policy for organization and the public offering of partnership interests.No definition available.false0Organization and offering costs11false 2us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-size:10.0pt;font-family:Times New Roman;"> Foreign currency transactions: The Partnership’s functional currency is the U.S. dollar; however, it transacts business in currencies other than the U.S. dollar. Assets and liabilities denominated in currencies other than the U.S. dollar are translated into U.S. dollars at the rates in effect at the date of the consolidated statement of financial condition. Income and expense items denominated in currencies other than the U.S. dollar are translated into U.S. dollars at the rates in effect during the period. Gains and losses resulting from the translation to U.S. dollars are reported in income currently.   The Partnership does not isolate that portion of the results of operations resulting from changes in foreign exchange rates on investments from fluctuations arising from changes in market prices of securities held. Such fluctuations are included with the net realized or unrealized gain or loss from investments. </div>falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for (1) transactions denominated in a currency other than the reporting enterprise's functional currency, (2) translating foreign currency financial statements that are incorporated into the financial statements of the reporting enterprise by consolidation, combination, or the equity method of accounting, and (3) remeasurement of the financial statements of a foreign reporting enterprise in a hyperinflationary economy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -URI http://asc.fasb.org/subtopic&trid=2175856 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 10 -URI http://asc.fasb.org/subtopic&trid=2175826 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -URI http://asc.fasb.org/subtopic&trid=2175892 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 52 -Paragraph 5, 7-20, 80 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false0Foreign currency transactions12false 2gpff_StatementOfCashFlowsPolicyTextBlockgpff_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-size:10.0pt;font-family:Times New Roman;"> Statement of cash flows: The Partnership has elected not to provide statements of cash flows as permitted by FASB ASC 230, Statement of Cash Flows. The Partnership noted that as of and for the periods ended June 30, 2013 and 2012, substantially all investments were highly liquid, all investments are carried at fair value, the Partnership carried no debt, and the statements of changes in partners’ capital (net asset value) is presented. </div>falsefalsefalsenonnum:textBlockItemTypenaDescribes an entity's accounting policy for statement of cash flows.No definition available.false0Statement of cash flows13false 2us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-size:10.0pt;font-family:Times New Roman;"> Recently adopted accounting pronouncements: In December 2011, the FASB issued ASU 2011-11-Balance Sheet (Topic 210) containing new guidance that requires an entity to disclose information about offsetting and related arrangements to enable users of its financial statements to understand the effect of those arrangements on its financial position. In January 2013, the FASB issued ASU 2013-01- Balance Sheet (Topic 210) clarifying the scope of disclosures about offsetting assets and liabilities. The guidance is effective for annual and interim periods beginning on or after January 1, 2013. An entity should provide the disclosures required by those amendments retrospectively for all comparative periods presented. The Partnership adopted ASU 2011-11 and 2013-01 as of January 1, 2013 and the adoption did not have a material impact on its consolidated financial statements. </div>falsefalsefalsenonnum:textBlockItemTypenaDisclosure of the adoption of new accounting pronouncements that may impact the entity's financial reporting.No definition available.false0Recently adopted accounting pronouncementsfalseNature of Business and Significant Accounting Policies (Policies)UnKnownUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.grantparkfunds.com/role/DisclosureNatureOfBusinessAndSignificantAccountingPoliciesPolicies113