Investment Securities - Additional Information (Detail) - CAD ($) $ in Millions |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Jul. 31, 2026 |
Apr. 30, 2026 |
Jul. 31, 2025 |
Jul. 31, 2026 |
Jul. 31, 2025 |
|
| Disclosure of detailed information about financial instruments [line items] | |||||
| Fair value of disposed equity securities | $ 6.0 | $ 87.0 | $ 25.0 | $ 93.0 | $ 1,839.0 |
| Cumulative after-tax gain/(loss) on equity securities designated at FVOCI | 0.1 | 87.0 | (27.0) | 87.0 | 512.0 |
| Dividend income | $ 1.0 | $ 8.0 | $ 1.0 | $ 9.0 | $ 46.0 |