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Leases - Narrative (Details) $ in Thousands |  |  |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  |
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Mar. 13, 2025 USD ($) ft² | Aug. 30, 2024 USD ($) ft² | May 07, 2024 USD ($) ft² | May 01, 2024 USD ($) extension_option | Feb. 28, 2024 USD ($) ft² | Nov. 13, 2023 operating_lease | Oct. 31, 2023 USD ($) ft² | Sep. 01, 2022 USD ($) ft² | Jul. 31, 2019 USD ($) ft² | Mar. 31, 2025 USD ($) | Mar. 31, 2024 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Oct. 24, 2022 USD ($) | Oct. 06, 2022 ft²
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease liabilities |  |  |  |  |  |  |  |  |  | $ 14,066 |  |  |  |  |  |
Right-of-use asset, net |  |  |  |  |  |  |  |  |  | $ 5,351 |  | $ 5,535 |  |  |  |
Operating lease, weighted average discount rate, percent |  |  |  |  |  |  |  | 11.30% |  | 11.80% | 9.90% |  |  |  |  |
Lessee-paid construction costs |  |  |  |  |  |  |  |  |  | $ 1,001 | $ 665 |  |  |  |  |
7495 New Horizon Way Leases |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Area of office space leased | ft² | 6,439 | 2,009 | 7,842 |  | 19,199 |  |  |  |  |  |  |  |  |  |  |
Lease term |  |  |  | 7 years 2 months 12 days |  |  |  |  |  |  |  |  |  |  |  |
Number of options to extend lease | extension_option |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |
Lease renewal term (in years) |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |
Lease agreement, monthly base rent |  |  |  | $ 900 |  |  |  |  |  |  |  |  |  |  |  |
Base rent upward annual adjustment percentage after first year | 3.00% | 3.00% | 3.00% | 3.00% |  |  |  |  |  |  |  |  |  |  |  |
Lease agreement, first month's rent paid upon execution of lease agreement |  |  |  |  | $ 100 |  |  |  |  |  |  |  |  |  |  |
Lease liabilities |  | $ 300 | $ 1,200 | $ 3,600 |  |  |  |  |  |  |  |  |  |  |  |
Right-of-use asset, net |  | 300 | 1,200 | 3,700 |  |  |  |  |  |  |  |  |  |  |  |
Tenant improvement recognized as reduction in right-of-use asset and lease liability |  |  | $ 100 | $ 700 |  |  |  |  |  |  |  |  |  |  |  |
Operating lease, weighted average discount rate, percent |  |  | 14.00% | 14.00% |  |  |  |  |  |  |  |  |  |  |  |
Additional annual base rent for first year | $ 200 | $ 100 | $ 300 |  |  |  |  |  |  |  |  |  |  |  |  |
7495 New Horizon Way Leases | Letter of Credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term restricted cash |  |  |  |  |  |  |  |  |  | 300 |  | 300 |  |  |  |
7495 New Horizon Way Leases | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating lease, cost (as a percent) |  |  |  | 100.00% |  |  |  |  |  |  |  |  |  |  |  |
7495 New Horizon Way Leases | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating lease, cost (as a percent) |  |  |  | 103.00% |  |  |  |  |  |  |  |  |  |  |  |
65 Grove Street Lease |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Area of office space leased | ft² |  |  |  |  |  |  | 5,600 | 7,216 | 25,078 |  |  |  |  |  |  | 7,216
Lease term |  |  |  |  |  |  |  | 5 years 8 months 12 days | 8 years |  |  |  |  |  |  |
Lease liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3,200 | $ 100 |
Right-of-use asset, net |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3,200 | $ 100 |
Operating lease, weighted average discount rate, percent |  |  |  |  |  |  |  |  | 8.90% |  |  |  |  |  | 11.90% |
Lessee-paid construction costs |  |  |  |  |  |  |  |  | $ 800 |  |  |  |  |  |  |
Operating lease, expense |  |  |  |  |  |  |  | $ 100 |  |  |  |  |  |  |  |
Upfront rental payment |  |  |  |  |  |  | $ 1,000 |  |  |  |  |  |  |  |  |
Right-of-use asset impairment expense |  |  |  |  |  |  |  |  |  |  |  | 7,400 | $ 700 |  |  |
Asset impairment charges |  |  |  |  |  |  |  |  |  |  |  | 7,600 |  |  |  |
Impairment of long-lived assets |  |  |  |  |  |  |  |  |  |  |  | 200 |  |  |  |
65 Grove Street Lease | Letter of Credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term restricted cash |  |  |  |  |  |  |  |  | $ 1,600 | $ 1,400 |  | $ 1,400 |  |  |  |
704 Quince Orchard Road Leases |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating lease, weighted average discount rate, percent |  |  |  |  |  | 11.50% |  |  |  |  |  |  |  |  |  |
Number of acquired operating leases | operating_lease |  |  |  |  |  | 2 |  |  |  |  |  |  |  |  |  |

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