Fair Value Measurements (Schedule of Reconciliation of Changes in Fair Value for Level 3 Assets and Liabilities) (Parenthetical) (Details) - CAD ($) $ in Millions |
Apr. 30, 2026 |
Jan. 31, 2026 |
Oct. 31, 2025 |
Apr. 30, 2025 |
Feb. 01, 2025 |
Jan. 31, 2025 |
Nov. 01, 2024 |
Oct. 31, 2024 |
|---|---|---|---|---|---|---|---|---|
| Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items] | ||||||||
| Derivative assets | $ 74,835 | $ 82,972 | ||||||
| Derivatives | 74,532 | 79,356 | ||||||
| Netted derivatives [member] | Level 3 of fair value hierarchy [member] | ||||||||
| Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items] | ||||||||
| Derivative assets | 76 | $ 25 | 11 | $ 32 | $ 38 | $ 38 | $ 30 | $ 30 |
| Derivatives | $ 225 | $ 225 | $ 291 | $ 265 | $ 205 | $ 205 | $ 221 | $ 221 |