Annual report pursuant to Section 13 and 15(d)

Cover
- Cover
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Warrant Liability (Details Narrative)

v3.24.1

Warrant Liability (Details Narrative) - USD ($)	12 Months Ended
Warrant Liability (Details Narrative) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jan. 04, 2023
Volatility amount utilized in the value calculation percentage		125.53%
Change in fair value of warrant liability	$ (4,797,000)	$ (119,000)
Change in fair value of the warrant liability	$ 4,700,000
Maximum [Member]
Volatility amount utilized in the value calculation percentage	123.61%
Common Warrants [Member] \| Maximum [Member]
Warrants to purchase				216,667
Placement Agent Warrant [Member] \| Maximum [Member]
Warrants to purchase				13,000
Purchase Warrant [Member]
Volatility amount utilized in the value calculation percentage	100.00%
Change in fair value of warrant liability	$ 5,800,000
Warrant [Member]
Change in fair value of warrant liability	1,100,000	19,000
2020 [Member]
Change in fair value of warrant liability	2,000	19,000	$ 138,000
Derivative liability	$ 17,000,000,000	$ 119,000,000,000

- Definition

Fair value derivative liabilities.

+ References

No definition available.

+ Details

Name:	GTBP_FairValueDerivativeLiabilities
Namespace Prefix:	GTBP_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Change in fair value of the warrant liability.

+ References

No definition available.

+ Details

Name:	GTBP_IncreaseDecreaseInFairValueOfWarrantLiability
Namespace Prefix:	GTBP_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-3

+ Details

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

- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 25
-Paragraph 13
-SubTopic 10
-Topic 480
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481766/480-10-25-13

+ Details

Name:	us-gaap_FairValueAdjustmentOfWarrants
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=GTBP_CommonWarrantsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=GTBP_PlacementAgentWarrantMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=GTBP_PurchaseWarrantMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_WarrantMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=GTBP_TwentyTwentyWarrantMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: