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Fees paid for services provided by an independent administrator for certain matters pertaining to the administration of the Fund.

+ References

No definition available.

+ Details

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- Details

Name:	gaifb_BrokerageFeesAbstract
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- Definition

Fees paid on services for investment advice, research and other services. Such services may include the investment management of mutual funds and separate accounts, and are generally based upon the size of the funds managed.

+ References

No definition available.

+ Details

Name:	gaifb_InvestmentAdvisoryFeePercentage
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- Definition

Amount paid to the advisor for management of the day-to-day business functions of the LLC or LP including the fee rate, basis of calculation, relevant accounting period, whether the fee is paid to an entity other than the managing member or General Partner, or whether the fee is waived.

+ References

No definition available.

+ Details

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- Definition

Incentive fees which are compensation paid to a trading advisor or to any practitioner who achieves investment results above a specified contractual level.

+ References

No definition available.

+ Details

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- Details

Name:	gaifb_SponsorFeesAbstract
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- Definition

Fees paid to advisors who provide certain management support and administrative oversight services including the organization and sale of stock, investment funds, limited partnerships and mutual funds.

+ References

No definition available.

+ Details

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Fees and Related Party Transactions (Details) (USD $)	3 Months Ended		9 Months Ended
Fees and Related Party Transactions (Details) (USD $)	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Fees and Related Party Transactions [Abstract]
Advisory fees at annual rate of net asset value of fund (in hundredths)	1.75%	2.00%	1.75%	2.00%
Percentage of incentive allocation (in hundredths)	20.00%	20.00%	20.00%	20.00%
Administrator's Fee [Abstract]
Administrator's fees	$ 26,724	$ 0	$ 86,812	$ 0
Class 0 Units [Member]
Sponsor Fees [Abstract]
Sponsor fees at annual rate of net asset value of fund (in hundredths)			0.75%	1.00%
Brokerage Fees [Abstract]
Brokerage fees at annual rate (in hundredths)				2.00%
Class 2 Units [Member]
Sponsor Fees [Abstract]
Sponsor fees at annual rate of net asset value of fund (in hundredths)			2.75%	1.00%
Brokerage Fees [Abstract]
Brokerage fees at annual rate (in hundredths)				4.00%