v3.25.1

Consolidated Statements of Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Statement of Stockholders' Equity [Abstract] |  |
Issuance costs | $ 3,436 | $ 272

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- Definition Common stock and pre-funded warrants issuance costs. + References No definition available. + Details
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Namespace Prefix: | fbrx_
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Balance Type: | debit
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- References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration