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Commitments, Guarantees, Pledged Assets, Provisions and Contingent Liabilities - Summary of Maximum Amounts Payable Under Various Commitments (Detail) - CAD ($) $ in Millions | Oct. 31, 2025 | Oct. 31, 2024
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Disclosure commitments guarantees pledged assets provisions and contingent liabilities [line items] |  |  |
Maximum potential amount of future payments |  | $ 322,294 | $ 307,633
Financial Guarantees [Member] | Standby letters of credit [member] |  |  |
Disclosure commitments guarantees pledged assets provisions and contingent liabilities [line items] |  |  |
Maximum potential amount of future payments |  | 29,409 | 30,523
Financial Guarantees [Member] | Credit default swaps [member] |  |  |
Disclosure commitments guarantees pledged assets provisions and contingent liabilities [line items] |  |  |
Maximum potential amount of future payments | [1] | 23,507 | 16,211
Other Credit Instruments [Member] | Backstop liquidity facilities [member] |  |  |
Disclosure commitments guarantees pledged assets provisions and contingent liabilities [line items] |  |  |
Maximum potential amount of future payments |  | 18,358 | 18,224
Other Credit Instruments [Member] | Documentary and commercial letters of credit [member] |  |  |
Disclosure commitments guarantees pledged assets provisions and contingent liabilities [line items] |  |  |
Maximum potential amount of future payments |  | 2,504 | 1,893
Other Credit Instruments [Member] | Commitments to extend credit [member] |  |  |
Disclosure commitments guarantees pledged assets provisions and contingent liabilities [line items] |  |  |
Maximum potential amount of future payments | [2] | 238,884 | 230,689
Other Credit Instruments [Member] | Other commitments [member] |  |  |
Disclosure commitments guarantees pledged assets provisions and contingent liabilities [line items] |  |  |
Maximum potential amount of future payments | [3] | $ 9,632 | $ 10,093
[1] | The fair value of the related derivatives included in our Consolidated Balance Sheet was $1 million as at October 31, 2025 ($8 million as at October 31, 2024).
[2] | Commitments to extend credit exclude personal lines of credit and credit cards that are unconditionally cancellable at our discretion.
[3] | Other commitments include $1,664 million as at October 31, 2025 ($4,511 million as at October 31, 2024) of underwriting commitments that are extended but not yet accepted by the borrower.

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