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v3.25.3

Basis of Presentation - Additional Information (Detail) - CAD ($) $ in Millions | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Oct. 31, 2025 | Oct. 31, 2024 | Oct. 31, 2023 | Nov. 01, 2022
Basis of presentation [line items] |  |  |  |
Contractual service margin | $ 1,210 | $ 1,370 |  | $ 1,550
Other assets | 42,884 | 42,387 |  |
Liabilities | 1,388,702 | 1,325,361 |  |
Assets | $ 1,476,802 | $ 1,409,647 |  |
Increase (decrease) due to changes in accounting policy required by IFRSs, cumulative effect at date of initial application [member] | Indian Accounting Standard Forty [Member] |  |  |  |
Basis of presentation [line items] |  |  |  |
Other assets |  |  |  | 132
Stockholders equity after tax |  |  |  | $ 132
Increase (decrease) due to changes in accounting policy required by IFRSs, cumulative effect at date of initial application [member] | IFRS 9 [member] |  |  |  |
Basis of presentation [line items] |  |  |  |
Liabilities |  |  | $ 52,500 |
Assets |  |  | $ 52,500 |
Bottom of range [member] |  |  |  |
Basis of presentation [line items] |  |  |  |
Proportion of voting rights held in associate | 20.00% |  |  |
Top of range [member] |  |  |  |
Basis of presentation [line items] |  |  |  |
Proportion of voting rights held in associate | 50.00% |  |  |
Useful lives of Intangible assets other than goodwill | 15 years |  |  |

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