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Significant accounting policies - Narrative (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Mar. 09, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Goodwill impairment charge | $ 0 | $ 0 | $ 0 |
Carrying value of inventory | $ 5,800,000 | $ 4,800,000 |  |
MeDiNova |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Business combination acquisition percentage (in percent) |  |  |  | 100.00%

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- Definition Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date. + References No definition available. + Details
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