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Net revenues - Schedule of Contract Cost Assets (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |  |
Opening balance |  |  | $ 200,900 |
Closing balance | $ 204,138 |  | 204,138 |
Sales incentive programs |  |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |  |
Opening balance | 36,486 | $ 40,252 | 41,348 | $ 41,964
Closing balance | 35,591 | 40,078 | 35,591 | 40,078
Amortization | 6,580 | 7,604 | 18,549 | 21,286
Transition activities |  |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |  |
Opening balance | 171,012 | 163,150 | 159,552 | 160,579
Closing balance | 168,547 | 160,362 | 168,547 | 160,362
Amortization | $ 22,428 | $ 20,060 | $ 60,711 | $ 57,075

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