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Assets and liabilities held for sale - Narrative (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Feb. 28, 2023 | Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2023 | Nov. 30, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Debt Instrument, Revised Redemption Period |  |  |  |  |  | 6 months
Loss on the sale of business classified as held for sale (refer to Note 7) |  | $ 0 | $ 802 |  |  |
Impairment charge on assets classified as held-for-sale |  |  | $ 802 |  |  |
The Business |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Percentage of issued and outstanding shares (in percent) |  |  |  |  | 100.00% |
Contingent consideration, asset |  |  |  |  | $ 10,600 |
Net consideration transferred | $ 2,091 |  |  |  |  |
Loss on the sale of business classified as held for sale (refer to Note 7) | $ 802 |  |  |  |  |
Impairment charge on assets classified as held-for-sale |  |  |  | $ 32,575 |  |
The Business | Fixed rate unsecured loan note |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |
Interest rate on senior notes (in percentage) |  |  |  |  | 1.50% |
Debt instrument, face amount |  |  |  |  | $ 18,001 |
Debt Instrument, Face Amount, Contingent Reduced Redemption Value |  | 1,500 |  |  |  | $ 1,500
Gain on extinguishment of debt |  | $ 1,500 |  |  |  |

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