Derivative Liabilities - Fair value assumptions, derivative additional investment rights liability (Details) (USD $)	0 Months Ended
Apr. 30, 2015	Jul. 31, 2014
Notes to Financial Statements
Underlying number of units of convertible preferred stock		2,075
Underlying number of units of warrants		69,166,667GNBT_WarrantsIssuable
Current exercise price of warrants	$ 0.03	$ 0.03
Current conversion price of preferred stock		$ 0.03
Time to expiration		7 months 24 days
Risk-free interest rate		0.0009GNBT_RiskfreeInterestRate
Estimated volatility		0.61GNBT_EstimatedVolatility
Dividend	0.00%	0.00%
Stock price at period end date	$ 0.0225us-gaap_SharePrice	$ 0.0210us-gaap_SharePrice

No authoritative reference available.

No definition available.

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- Definition

Preferred Stock Conversion Price Per Share

+ References

No definition available.

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- Definition

No authoritative reference available.

+ References

No definition available.

+ Details

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- Definition

No authoritative reference available.

+ References

No definition available.

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- Definition

Warrants Issuable

+ References

No definition available.

+ Details

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- Definition

The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

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- Definition

Agreed upon price for the exchange of the underlying asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

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- Definition

Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price).

+ References

+ Details

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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