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Share capital - Narrative (Details) - USD ($) $ in Thousands |  |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 19, 2025 | Nov. 07, 2024 | Oct. 31, 2024 | Sep. 25, 2024 | Mar. 31, 2025 | Dec. 19, 2024 | Mar. 31, 2025 | Dec. 31, 2024 | Feb. 18, 2025 | Oct. 22, 2024
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Stock repurchase program, additional amount authorized |  |  |  |  |  |  |  |  | $ 750,000 |
Stock repurchase program, authorized amount |  |  |  |  |  |  |  |  | $ 1,000,000 | $ 250,000
Total number of shares purchased (in shares) | 1,360,537 | 479,524 | 409,512 | 337,070 | 1,360,537 | 953,593 |  | 2,179,699 |  |
Share repurchase program, value of shares repurchased |  |  |  |  | $ 250,000 |  | $ 250,000 | $ 500,000 |  |
Approximate dollar value of shares that may yet be purchased under the program (in millions) | $ 750,000 | $ 450,000 | $ 556,400 | $ 400,000 | $ 750,000 | $ 250,000 | $ 750,000 |  |  |
Maximum |  |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Share repurchase program, authorized percentage |  |  |  |  |  |  | 10.00% |  |  |

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