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Leases - Narrative (Details) ft² in Thousands, $ in Thousands | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2025 USD ($) | Jun. 30, 2025 USD ($) | Jun. 01, 2025 ft² | Dec. 31, 2024 USD ($)
Lessee, Lease, Description [Line Items] |  |  |  |
Lease term |  |  | 45 months |
Operating lease right-of-use assets | $ 1,607 | $ 1,607 |  | $ 0
Operating lease liability, current | 211 | 211 |  | 0
Operating lease liability, noncurrent | $ 1,433 | $ 1,433 |  | $ 0
Remaining lease term | 3 years 8 months 12 days | 3 years 8 months 12 days |  |
Operating lease, discount rate | 10.60% | 10.60% |  |
Operating lease, expense | $ 100 | $ 100 |  |
Waltham, Massachusetts | Building |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |
Area of office space (in sqft) | ft² |  |  | 25 |

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- Definition Remaining lease term of operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-3 + Details
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