Stock-based compensation - Schedule of Options Exercised (Details) - Stock Option Plan - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value	$ 101	$ 53	$ 43
Cash received by the Company upon exercise of options	$ 69	$ 32	$ 25

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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+ Details