Fair Value Measurements - Hierarchy (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Fair value assets and liabilities
Warrant derivative liability	$ 3,274	$ 6,633
Level 1
Fair value assets and liabilities
Fair value money market accounts	30,310	29,036
Recurring
Fair value assets and liabilities
Warrant derivative liability	3,274	6,633
Recurring \| BTI Warrants
Fair value assets and liabilities
Warrant derivative liability	3,236	6,593
Recurring \| OnkosXcel Warrants
Fair value assets and liabilities
Warrant derivative liability	38	40
Recurring \| Level 2
Fair value assets and liabilities
Warrant derivative liability	1,834	6,593
Recurring \| Level 2 \| BTI Warrants
Fair value assets and liabilities
Warrant derivative liability	1,834	6,593
Recurring \| Level 3
Fair value assets and liabilities
Warrant derivative liability	1,440	40
Recurring \| Level 3 \| BTI Warrants
Fair value assets and liabilities
Warrant derivative liability	1,402
Recurring \| Level 3 \| OnkosXcel Warrants
Fair value assets and liabilities
Warrant derivative liability	38	40
Recurring \| Fair Value
Fair value assets and liabilities
Warrant derivative liability	3,274	6,633
Recurring \| Fair Value \| BTI Warrants
Fair value assets and liabilities
Warrant derivative liability	3,236	6,593
Recurring \| Fair Value \| OnkosXcel Warrants
Fair value assets and liabilities
Warrant derivative liability	$ 38	$ 40

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
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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
-Subparagraph (c)
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+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-3

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