Document And Entity Information	9 Months Ended
Sep. 30, 2011	Oct. 01, 2011 Blended Strategies Portfolio [Member]	Oct. 01, 2011 Systematic Strategies Portfolio [Member]
Entity Information [Line Items]
Entity Registrant Name	GRAHAM ALTERNATIVE INVESTMENT FUND II LLC
Entity Central Index Key	0001461237
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Smaller Reporting Company
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q3
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2011
Entity Common Stock, Shares Outstanding		1,359,825.669	296,647.984

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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