| Contingencies and commitments - MD Anderson Strategic Alliance (Details) - MD Anderson Strategic Alliance - USD ($) | 12 Months Ended | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Dec. 02, 2024 | Mar. 23, 2022 | Dec. 31, 2024 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2018 | Dec. 31, 2017 | Sep. 26, 2016 | |
| Contingencies and commitments | |||||||||
| Upfront payment | $ 3,412,000 | ||||||||
| Milestone payment | $ 2,326,000 | $ 454,000 | $ 3,549,000 | $ 2,326,000 | |||||
| Total remaining clinical milestones | $ 4,070,000 | ||||||||
| Amount of remaining billing upon completion | $ 452,000 | ||||||||
| Damages claims on breach of contract | $ 21,000,000 | ||||||||
| Provision for a loss contingency | $ 0 | ||||||||
| Minimum | |||||||||
| Contingencies and commitments | |||||||||
| Potential milestone payments | $ 19,644,000 | ||||||||
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- Definition Represents the amount of payments that the entity is required to make under the agreement, upon achievement of certain development and product milestones. No definition available. 
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- Definition Represents the amount of milestone payments that will not be met or paid. No definition available. 
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- Definition Represents the amount of payments that the entity is required to make under the agreement, upon achievement of certain development and product milestones. No definition available. 
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- Definition Represents the remaining amount of billing. No definition available. 
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- Definition Amount of up-front payment under terms of the agreement. No definition available. 
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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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- Definition Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- Definition The value (monetary amount) of the award the plaintiff seeks in the legal matter. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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