Accounts Payable (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Accounts Payable [Abstract]
Accounts payable, current	$ 277	$ 667
Legal and patent fees	200	100
Clinical trial expenses	$ 100
Drug manufacturing, development and testing expenses		$ 600

Carrying value as of the balance sheet date of clinical trial expenses incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

No definition available.

+ Details

Name:	bpth_ClinicalTrialExpensesPayable
Namespace Prefix:	bpth_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of drug manufacturing, development and testing expenses incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

+ References

No definition available.

+ Details

Name:	bpth_DrugManufacturingDevelopmentAndTestingExpensesPayable
Namespace Prefix:	bpth_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of legal and patent fees incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

+ References

No definition available.

+ Details

Name:	bpth_LegalAndPatentFeesPayable
Namespace Prefix:	bpth_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481372/852-10-55-10

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant