Consolidated Statements of Financial Condition (Unaudited) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Assets
Investment in Graham Alternative Investment Trading LLC, at fair value	$ 83,925,493us-gaap_InvestmentOwnedAtFairValue	$ 78,546,247us-gaap_InvestmentOwnedAtFairValue
Redemption receivable from Graham Alternative Investment Trading LLC	626,716gaifb_RedemptionReceivable	2,719,033gaifb_RedemptionReceivable
Total assets	84,552,209us-gaap_Assets	81,265,280us-gaap_Assets
Liabilities:
Accrued redemptions	626,716gaifb_AccruedRedemptions	2,719,033gaifb_AccruedRedemptions
Total liabilities	626,716us-gaap_Liabilities	2,719,033us-gaap_Liabilities
Members' capital:
Members' capital	83,925,493us-gaap_PartnersCapital	78,546,247us-gaap_PartnersCapital
Total liabilities and members' capital	84,552,209	81,265,280
Class 0 Units [Member]
Members' capital:
Members' capital	62,700,318	58,300,841
Class 2 Units [Member]
Members' capital:
Members' capital	$ 21,225,175	$ 20,245,406

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