Post-Employment Benefits - Summary of Defined Contributions Plan Expense (Detail) - CAD ($) $ in Millions |
3 Months Ended | ||
|---|---|---|---|
Jan. 31, 2023 |
Oct. 31, 2022 |
Jan. 31, 2022 |
|
| Disclosure of defined contribution plans [line items] | |||
| Expense recognized in consolidated statement of income | $ 67 | $ 53 | $ 58 |
| Defined contribution pension plans [member] | |||
| Disclosure of defined contribution plans [line items] | |||
| Expense recognized in consolidated statement of income | 19 | 11 | 17 |
| Government pension plans [member] | |||
| Disclosure of defined contribution plans [line items] | |||
| Expense recognized in consolidated statement of income | $ 48 | $ 42 | $ 41 |