Derivative financial instruments and hedging activities - Summary of Effectiveness of Designated Hedging Relationships (Parenthetical) (Detail) - CAD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Oct. 31, 2022 |
Oct. 31, 2021 |
|
| Changes in the value of the hedging instrument recognized in income [member] | Excluded from assessment of hedge effectiveness and offset by economic hedges [member] | ||
| Disclosure of information about amounts that affected statement of comprehensive income as result of hedge accounting [line items] | ||
| Hedging loss | $ 19 | $ 101 |