| Contingencies and commitments - Clinical Trials and Contract Manufacturing Commitments (Details) - Clinical trials and contract manufacturing commitments - USD ($) | 12 Months Ended | ||
|---|---|---|---|
| Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | |
| Contingencies and commitments | |||
| Subcontract costs | $ 48,416,000 | $ 54,689,000 | $ 33,744,000 | 
| Other commitments, due within one year | 12,408,000 | ||
| Other commitments, due in one to three years | 1,268,000 | ||
| Other commitments, due in three to five years | 70,000 | ||
| Maximum | |||
| Contingencies and commitments | |||
| Other commitments | $ 13,746,000 | ||
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- Definition Amount of other commitments maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available. 
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- Definition Amount of other commitments maturing in the second or third rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available. 
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- Definition Amount of other commitments maturing in the fourth or fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available. 
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- Definition Amount of subcontract costs incurred during the period. No definition available. 
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- Definition Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions. No definition available. 
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- References No definition available. 
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- Details 
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