Segment Reporting - Segment Profit or Loss and Segment Expenses (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||||
|---|---|---|---|---|---|---|
Jun. 30, 2026 |
Mar. 31, 2026 |
Jun. 30, 2025 |
Mar. 31, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Segment Reporting [Line Items] | ||||||
| Collaboration revenue - related party | $ 4,640 | $ 0 | $ 4,640 | $ 0 | ||
| Significant operating expenses: | ||||||
| Total operating expenses | 51,560 | 56,819 | 97,652 | 122,010 | ||
| Other income (expenses), net | 4,243 | 5,876 | 7,728 | 11,334 | ||
| Net loss | (42,677) | $ (42,607) | (50,943) | $ (59,733) | (85,284) | (110,676) |
| Reportable Segment | ||||||
| Segment Reporting [Line Items] | ||||||
| Collaboration revenue - related party | 4,640 | 0 | 4,640 | 0 | ||
| Significant operating expenses: | ||||||
| Cema-cel | 6,954 | 6,865 | 14,623 | 13,087 | ||
| All other development costs | 2,408 | 4,896 | 4,407 | 15,286 | ||
| Payroll | 14,482 | 17,628 | 28,926 | 37,229 | ||
| Facilities & IT-related spend | 7,288 | 7,384 | 13,706 | 14,703 | ||
| Supporting external spend | 5,254 | 5,390 | 9,626 | 11,236 | ||
| Other operating expenses | 15,174 | 14,656 | 26,364 | 30,469 | ||
| Total operating expenses | 51,560 | 56,819 | 97,652 | 122,010 | ||
| Other income (expenses), net | 4,243 | 5,876 | 7,728 | 11,334 | ||
| Net loss | $ (42,677) | $ (50,943) | $ (85,284) | $ (110,676) | ||
| X | ||||||||||
- Definition Facilities And IT-Related Expense No definition available.
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- Definition Research And Development Expense, Cema-cel No definition available.
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- Definition Research And Development Expense, Other Development Costs No definition available.
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- Definition Supporting External Spend Expense No definition available.
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- Definition Amount of expense for salary, wage, profit sharing; incentive and equity-based compensation; and other employee benefit. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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