Segment Reporting - Additional Information (Details) $ in Millions	12 Months Ended
Dec. 31, 2024 USD ($) Segment	Dec. 31, 2023 USD ($)
Segment Reporting Information [Line Items]
Number of operating business segment \| Segment	1
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]	srt:ChiefExecutiveOfficerMember
Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description	The CODM assesses the performance of the Company and decides how to allocate resources based upon net loss that is also reported within the Consolidated Statements of Operations. The measure of segment assets that is reviewed by the CODM is reported within the Consolidated Balance Sheet as total assets.
Severance expense \| $	$ 0.0	$ 7.9
Revenue \| UCB \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Percentage revenue from customers	39.00%	40.00%
Revenue \| Baxalta Incorporated Or Takeda P L C \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Percentage revenue from customers	18.00%	21.00%
Revenue \| Astra Zeneca Ab \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Percentage revenue from customers	17.00%	11.00%
Revenue \| Pfizer \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Percentage revenue from customers	12.00%	10.00%
Revenue \| Roche \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Percentage revenue from customers	10.00%

Number of operating business segment.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Indicates title and position of individual or name of group identified as chief operating decision maker (CODM) for segment reporting.

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- Definition

Description of how chief operating decision maker (CODM) uses reported segment profit (loss) measure to assess performance and allocate resource.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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