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Restructuring (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
Restructuring (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Sep. 30, 2025	Dec. 31, 2024
Restructuring Cost and Reserve [Line Items]
Restructuring liabilities		$ (763)	$ 0
Restructuring And Workforce Reduction
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, number of positions eliminated, percent	57.00%
Impairment of leasehold improvements		1,900
Impairment of laboratory equipment		900
Operating Lease, Impairment Loss		900
Restructuring And Workforce Reduction \| Employee Severance
Restructuring Cost and Reserve [Line Items]
Cash severance		6,100
Restructuring liabilities		(500)
Restructuring And Workforce Reduction \| Modification of Equity Awards
Restructuring Cost and Reserve [Line Items]
Noncash modification of equity awards		2,400
Restructuring And Workforce Reduction \| Accrual of lease-related operating expenses
Restructuring Cost and Reserve [Line Items]
Accrued lease-related operating expenses		(400)
Restructuring liabilities		$ (300)