Schedule of Derivative Liability Transactions (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Beginning balance	$ 115,000	$ 842,000	$ 138,000	$ 383,000
Issuance of warrants
Change in fair value	(58,000,000)	(502,000,000)	(81,000,000)	(43,000,000)
Extinguishment
Ending balance	$ 57,000	$ 340,000	$ 57,000	$ 340,000

Extinguishment of warrants.

No definition available.

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Namespace Prefix:	GTBP_
Data Type:	xbrli:monetaryItemType
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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

+ Details

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- References

No definition available.

+ Details

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- Definition

The increase (decrease) during the period in the carrying value of derivative instruments reported as liabilities that are due to be disposed of within one year (or the normal operating cycle, if longer).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

+ Details

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- Definition

Fair value of share-based compensation granted to nonemployees as payment for services rendered or acknowledged claims.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

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