v3.25.1

Subsequent Events - Additional Information (Details)	1 Months Ended
	Jan. 31, 2025 shares
Subsequent Event | Pre funded warrants | 2023 Private Placement
Subsequent Event [Line Items]
Warrants exercised	185,732

X

- Definition

Class of warrant or right number of securities called by warrants exercised.

+ References

No definition available.

+ Details

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Namespace Prefix:	fbrx_
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Balance Type:	na
Period Type:	duration

X

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481674/830-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

+ Details

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Balance Type:	na
Period Type:	duration

X

- Details

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X

- Details

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Namespace Prefix:
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Period Type:

X

- Details

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