2.4.0.8070200 - Disclosure - Summary of Significant Accounting Policies (Policies)truefalsefalse1false falsefalsec20130101to20130630http://www.sec.gov/CIK0001461237duration2013-01-01T00:00:002013-06-30T00:00:001true 1us-gaap_AccountingPoliciesAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Summary of Significant Accounting Policies [Abstract]2false 2us-gaap_BasisOfAccountingPolicyPolicyTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalselabel1falsefalsefalse00<div style="font-family: 'Times New Roman', Times, serif; font-size: 10pt;"><div style="text-align: justify; text-indent: 0pt; display: block; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; margin-right: 0pt;">These consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles (“U.S. GAAP”) and all amounts are stated in U.S. dollars. The preparation of these consolidated financial statements requires the Manager to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates.</div></div>falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for basis of accounting, or basis of presentation, used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).No definition available.false0Basis of Accounting3false 2us-gaap_UseOfEstimatesus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-family: 'Times New Roman', Times, serif; font-size: 10pt;"><div style="text-align: justify; text-indent: 0pt; display: block; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; margin-right: 0pt;">These consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles (“U.S. GAAP”) and all amounts are stated in U.S. dollars. The preparation of these consolidated financial statements requires the Manager to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates.</div></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_ConsolidationPolicyTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalselabel1falsefalsefalse00<div style="font-family: 'Times New Roman', Times, serif; font-size: 10pt;"><div style="text-align: left; text-indent: 0pt; display: block; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; font-weight: bold; margin-right: 0pt;">Principles of Consolidation</div><div style="text-align: justify; text-indent: 0pt; display: block; margin-left: 0pt; margin-right: 0pt;"> </div><div style="text-align: justify; text-indent: 0pt; display: block; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; margin-right: 0pt;">The Fund owns 100% of GAI’s Blended Strategies Portfolio and as such these consolidated financial statements include all the accounts of the Fund and GAI’s Blended Strategies Portfolio. Intercompany transactions and balances have been eliminated in consolidation. Creditors of the Fund have recourse to all assets of the Fund for amounts due to them, while creditors of GAI would have recourse only to the assets of GAI.</div></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 false0Principles of Consolidation5false 2us-gaap_FairValueMeasurementPolicyPolicyTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00<div style="font-family: 'Times New Roman', Times, serif; font-size: 10pt;"><div style="text-align: justify; text-indent: 0pt; display: block; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; font-weight: bold; margin-right: 0pt;">Fair Value</div><div style="text-align: justify; text-indent: 0pt; display: block; margin-left: 0pt; margin-right: 0pt;"> </div><div style="text-align: justify; text-indent: 0pt; display: block; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; margin-right: 0pt;">The fair value of the assets and liabilities of the Fund and GAIT, which qualify as financial instruments under U.S. GAAP, approximates the carrying amounts presented in the consolidated statements of financial condition. Changes in these carrying amounts are included in the consolidated statements of operations.</div><div style="text-align: justify; text-indent: 0pt; display: block; margin-left: 0pt; margin-right: 0pt;"> </div><div style="text-align: justify; text-indent: 0pt; display: block; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; margin-right: 0pt;">The Fund follows U.S. GAAP for fair value measurements, which defines fair value, establishes a framework for measuring fair value, and requires certain disclosures about fair value measurements. U.S. GAAP uses a three-level hierarchy for fair value measurement based on the activeness of the market and the transparency and independence of inputs used in the valuation of an asset or liability as of the measurement date.</div><div style="text-align: justify; text-indent: 0pt; display: block; margin-left: 0pt; margin-right: 0pt;"> </div><div style="text-align: justify; text-indent: 0pt; display: block; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; margin-right: 0pt;">The fair value hierarchy categorizes asset and liability positions into one of three levels, as summarized below, based on the inputs and assumptions used in deriving fair value.</div><div style="text-indent: 0pt; display: block;"><br /></div><div><table align="center" border="0" cellpadding="0" cellspacing="0" style="width: 100%; font-family: times new roman; font-size: 10pt;"><tr valign="top"><td style="width: 18pt;"><div style="display: inline; font-family: Times New Roman; font-size: 10pt;"></div></td><td style="width: 18pt;"><div style="text-indent: 0pt; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; margin-right: 0pt;">·</div></td><td><div style="text-align: justify; font-family: Times New Roman; font-size: 10pt;">Level 1 inputs are unadjusted closing or settlement prices for such assets or liabilities as published by the primary exchange upon which they are traded.</div></td></tr></table></div><div><table align="center" border="0" cellpadding="0" cellspacing="0" style="width: 100%; font-family: times new roman; font-size: 10pt;"><tr valign="top"><td style="width: 18pt;"><div style="display: inline; font-family: Times New Roman; font-size: 10pt;"></div></td><td style="width: 18pt;"><div style="text-indent: 0pt; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; margin-right: 0pt;">·</div></td><td><div style="text-align: justify; font-family: Times New Roman; font-size: 10pt;">Level 2 inputs include quoted prices for similar assets and liabilities obtained from independent brokers and/or market makers in each security. With respect to the Fund’s investment in GAIT, Level 2 inputs include the net asset value of the underlying fund in which it holds an investment.</div></td></tr></table></div><div><table align="center" border="0" cellpadding="0" cellspacing="0" style="width: 100%; font-family: times new roman; font-size: 10pt;"><tr valign="top"><td style="width: 18pt;"><div style="display: inline; font-family: Times New Roman; font-size: 10pt;"></div></td><td style="width: 18pt;"><div style="text-indent: 0pt; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; margin-right: 0pt;">·</div></td><td><div style="text-align: justify; font-family: Times New Roman; font-size: 10pt;">Level 3 inputs are those which are considered unobservable and are significant in arriving at fair value.</div></td></tr></table></div><div style="text-indent: 0pt; display: block;"><br /></div><div style="text-align: justify; text-indent: 0pt; display: block; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; margin-right: 0pt;">The Fund reports the fair value of its investment related assets and liabilities in accordance with the hierarchy established under U.S. GAAP. In accordance with this hierarchy, the Fund’s investment in GAIT has been classified as a Level 2 valuation. There were no Level 3 assets or liabilities held at any point during the six month period ended June 30, 2013 or the twelve month period ended December 31, 2012 by the Fund, GAIT, or the Master Funds, and there were no transfers between levels during those periods. Transfers between levels, if any, are recognized on the actual date of the event or change in circumstances that cause the transfer.</div></div>falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for fair value measurements, which may include, but is not limited to, how an entity that manages a group of financial assets and liabilities on the basis of its net exposure measures the fair value of those assets and liabilities.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 820 -SubTopic 10 -Section 35 -Paragraph 18G -URI http://asc.fasb.org/extlink&oid=15229074&loc=SL7494712-110257 false0Fair Value6false 2gaifb_IndemnificationsPolicyPolicyTextBlockgaifb_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-family: 'Times New Roman', Times, serif; font-size: 10pt;"><div style="text-align: left; text-indent: 0pt; display: block; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; font-weight: bold; margin-right: 0pt;">Indemnifications</div><div style="text-align: justify; text-indent: 0pt; display: block; margin-left: 0pt; margin-right: 0pt;"> </div><div style="text-align: justify; text-indent: 0pt; display: block; font-family: Times New Roman; margin-left: 0pt; font-size: 10pt; margin-right: 0pt;">In the normal course of business, the Fund, GAIT, Graham Cash Assets LLC (“Cash Assets”), and the Master Funds enter into contracts that contain a variety of indemnifications. Such contracts may include those by Cash Assets and the Master Funds with their brokers and trading counterparties. The Fund’s maximum exposure under these arrangements is unknown; however, the Fund has not had prior claims or losses with respect to such indemnifications and considers the risk of loss to be remote.</div></div>falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for indemnification.No definition available.false0IndemnificationsfalseSummary of Significant Accounting Policies (Policies)UnKnownUnKnownUnKnownUnKnowntruefalsefalseSheethttp://grahamgaifb.com/role/SummaryOfSignificantAccountingPoliciesPolicies16