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Transfers of Financial Assets - Additional Information (Detail) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Oct. 31, 2025 | Oct. 31, 2024
Disclosure of transferred financial assets that are not derecognised in their entirety [line items] |  |
Sale of mortgage loans | $ 4,621 | $ 3,687
Securities lent | 15,011 | 12,913
Collateralized Mortgage Obligations at fair value | 6 | 6
Securities Sold Under Repurchase Agreement | 119,956 | 97,878
United States [member] |  |
Disclosure of transferred financial assets that are not derecognised in their entirety [line items] |  |
Sale of mortgage loans | 849 | 10,249
Carry value of Mortgage servicing rights | 146 | 169
Fair value of Mortgage serving rights | 170 | 192
Gain of derecognised financial assets at date of transfer | 24 | (153)
United States [member] | Residual Interests of Commercial Mortgage Loans [Member] |  |
Disclosure of transferred financial assets that are not derecognised in their entirety [line items] |  |
Proceeds from continuing involvement in derecognised financial assets | 3,863 | 4,412
Gain of derecognised financial assets at date of transfer | 44 | 49
Debt securities at amortized cost | 7 | 7
Loans carried at amortized cost | 92 | 40
NHA MBS Program [Member] | Canada [member] | Residential Mortgages [Member] |  |
Disclosure of transferred financial assets that are not derecognised in their entirety [line items] |  |
Sale of mortgage loans | 3,019 | 2,157
Collateralized Mortgage Obligations at fair value | 145 | 146
Gain of derecognised financial assets at date of transfer | $ (1) | $ 90

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- Definition Securities Sold Under Repurchase Agreement. + References No definition available. + Details
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + References No definition available. + Details
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- Definition The fair value of assets representing the entity's continuing involvement in derecognised financial assets. [Refer: Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 42E -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_42E_b&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of proceeds recognised from the transfer of financial assets during the part of the reporting period within which the greatest transfer activity took place when the total amount of proceeds from the transfer activity (that qualifies for derecognition) is not evenly distributed throughout the reporting period. [Refer: Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 42G -Subparagraph c -Clause iii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_42G_c_iii&doctype=Standard -URIDate 2024-03-27 + Details
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