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v3.25.3

Subordinated Debt - Summary of Maturities of Subordinated Debt and Repayment (Parenthetical) (Detail) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Oct. 31, 2025 CAD ($) | Oct. 31, 2024 CAD ($) | Oct. 31, 2025 $ / shares | Mar. 05, 2025 CAD ($)
Subordinated Liabilities [Line Items] |  |  |  |
Repayments of subordinated liabilities | $ 1,250 | $ 1,000 |  |
Subordinated liabilities | 8,500 | 8,377 |  |
Subordinated debt [member] |  |  |  |
Subordinated Liabilities [Line Items] |  |  |  |
Increase (Decrease) in Subordinated Long Term Debt | (304) | (400) |  |
Subordinated liabilities | $ 8,500 | 8,377 |  |
Bottom of range [member] | Subordinated debt [member] |  |  |  |
Subordinated Liabilities [Line Items] |  |  |  |
Common stock conversion price | $ / shares |  |  | $ 5 |
3.803% Subordinated Notes due 2032 [member] |  |  |  |
Subordinated Liabilities [Line Items] |  |  |  |
Borrowings, interest rate basis | 5-year mid-swap rate plus the reset premium noted. |  |  |
3.803% Subordinated Notes due 2032 [member] | Subordinated debt [member] |  |  |  |
Subordinated Liabilities [Line Items] |  |  |  |
Interest rate | 3.803% |  |  |
Subordinated liabilities | $ 1,656 | 1,602 |  |
Series J Medium Term Notes Second Tranche [Member] | Subordinated debt [member] |  |  |  |
Subordinated Liabilities [Line Items] |  |  |  |
Interest rate | 2.077% |  |  |
Repayments of subordinated liabilities | $ 1,250 |  |  |
Percentage of redemption of principal amount plus unpaid accrued interest | 100.00% |  |  |
Subordinated liabilities |  | 1,237 |  |
Series M Medium-Term Notes, Second Tranche [member] | Subordinated debt [member] |  |  |  |
Subordinated Liabilities [Line Items] |  |  |  |
Interest rate | 4.976% |  |  |
Subordinated liabilities | $ 999 | $ 999 |  |
Series M Medium-Term Notes, Second Tranche [member] | Unsecured Subordinated Debt [Member] |  |  |  |
Subordinated Liabilities [Line Items] |  |  |  |
Subordinated debt earliest date of redemption at par value | Mar. 05, 2030 |  |  |
Subordinated liabilities |  |  |  | $ 1,250

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