No definition available.

Name:	GNBT_NumberOfWarrantsIssuedAndExercised
Namespace Prefix:	GNBT_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of warrants or rights outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_ClassOfWarrantOrRightOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of warrants or rights which entitle the entity to receive future services in exchange for the unvested, forfeitable warrants or rights.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 50
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6784392&loc=d3e188667-122775

+ Details

Name:	us-gaap_ClassOfWarrantOrRightUnissued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_AwardTypeAxis=GNBT_SeriesDWarrantsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Warrants (Details Narrative) - $ / shares	Oct. 31, 2020	Oct. 12, 2020	Sep. 28, 2020	Aug. 04, 2020	Jul. 31, 2020
Warrants outstanding	60,772,618				567,553
Warrants issued			29,592,825	30,612,240
Exercise price	$ 0.24				$ 250
Series D Warrants [Member]
Number of Warrants issued and exercised	9,142,973	3,480,783	5,662,190
Exercise price		$ 0.001	$ 0.001