Consolidated Statements of Financial Condition (USD $)	Dec. 31, 2014	Dec. 31, 2013
Assets
Investment in Graham Alternative Investment Trading LLC, at fair value	$ 78,546,247us-gaap_InvestmentOwnedAtFairValue	$ 76,659,546us-gaap_InvestmentOwnedAtFairValue
Redemption receivable from Graham Alternative Investment Trading LLC	2,719,033gaifb_RedemptionReceivable	1,779,202gaifb_RedemptionReceivable
Total assets	81,265,280us-gaap_Assets	78,438,748us-gaap_Assets
Liabilities:
Accrued redemptions	2,719,033gaifb_AccruedRedemptions	1,779,202gaifb_AccruedRedemptions
Total liabilities	2,719,033us-gaap_Liabilities	1,779,202us-gaap_Liabilities
Members' capital:
Members' capital	78,546,247us-gaap_PartnersCapital	76,659,546us-gaap_PartnersCapital
Total liabilities and members' capital	81,265,280	78,438,748
Class 0 Units [Member]
Members' capital:
Members' capital	58,300,841	58,310,022
Class 2 Units [Member]
Members' capital:
Members' capital	$ 20,245,406	$ 18,349,524

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