Income taxes - Schedule of Income Taxes Paid (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Effective Income Tax Rate Reconciliation [Line Items]
Swiss	$ 0	$ 0	$ 0
Income taxes paid	369	302	211
U.S.
Effective Income Tax Rate Reconciliation [Line Items]
Foreign	230	196	142
Canada
Effective Income Tax Rate Reconciliation [Line Items]
Foreign	$ 139	$ 106	$ 69

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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