Parent company information - Summary of Parent Company Information - Condensed Statements of Income and Comprehensive Income (Parenthetical) (Detail) - CAD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Oct. 31, 2024 |
Oct. 31, 2023 |
|
| Parent [member] | ||
| Parent company information [line items] | ||
| Dividend income from investments in subsidiaries | $ 9 | $ 25 |