v3.25.1

Fair Value Measurements - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2025 USD ($) yr shares	Dec. 31, 2024 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants to purchase common stock \| shares	311,996
Fair value of warrants	$ 295	$ 516
Fair value of warrant assumptions, dividends	$ 0
Valuation Technique, Option Pricing Model \| Measurement Input, Risk Free Interest Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement input	0.042
Valuation Technique, Option Pricing Model \| Measurement Input, Price Volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement input	0.878
Valuation Technique, Option Pricing Model \| Measurement Input, Expected Term
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement input \| yr	9.5

Fair value of warrant assumptions, dividends.

+ References

No definition available.

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- 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

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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 after one year or the 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
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
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-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
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- Definition

Value of input used to measure outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
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89bio, Inc. 10-Q