Financial risk management - Translation exposure (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Financial risk management [Line Items]
Percentage of gains losses on exchange differences on translation recognised in profit or loss	10.00%
Canadian dollar
Financial risk management [Line Items]
Impact of 10% change in foreign exchange rates	$ 30.5	$ 23.7

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

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