Commitments and Contingencies - Lease costs (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Lease costs
Operating lease cost	$ 536	$ 441	$ 1,582	$ 1,323
Short-term lease cost	3	8	9	28
Variable lease cost	277	299	870	895
Total lease cost	816	$ 748	2,461	$ 2,246
Assets
Right-of-use asset - operating leases	11,135		11,135		$ 10,766
Liabilities
Operating lease liability, current	1,314		1,314		864
Operating lease liabilities, net of current portion	16,847		16,847		17,170
Total operating lease liabilities	$ 18,161		$ 18,161		$ 18,034
Other information
Weighted-average remaining lease term (in years)	9 years 7 months 6 days		9 years 7 months 6 days		10 years 8 months 12 days
Weighted-average incremental borrowing rate	7.10%		7.10%		7.00%

Operating Lease Asset [Abstract]

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Operating Lease, Other Information [Abstract]

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of lessee's right to use underlying asset under operating lease.

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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