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General and significant accounting policies (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2024 | Dec. 31, 2023 | Jul. 01, 2023
General and significant accounting policies [Line Items] |  |  |
Goodwill, Period Increase (Decrease) | $ 10 |  |
Huatai Group |  |  |
General and significant accounting policies [Line Items] |  |  |
Subsidiary, Ownership Percentage, Parent | 85.50% | 76.50% | 69.60%

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- Definition General and significant accounting policies + References No definition available. + Details
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- Definition Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482573/350-20-50-1 + Details
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- Details
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