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Loans and Allowance for Credit Losses - Schedule of Loans and Allowance for Credit Losses by Geographic Region (Detail) - CAD ($) $ in Millions | Oct. 31, 2025 | Oct. 31, 2024
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Disclosure of detailed information about financial instruments [line items] |  |
Loans, Gross amount | $ 682,211 | $ 682,372
ACL | 5,739 | 4,936
Loans, Net amount | 677,161 | 678,016
Allowance for credit losses related to loans [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Loans, Gross amount | 682,211 | 682,372
Loans, Net amount | 677,161 | 678,016
Allowance for credit losses related to loans [member] | Related to impaired loans [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
ACL | 974 | 653
Allowance for credit losses related to loans [member] | Related to performing loans [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
ACL | 4,076 | 3,703
Allowance for credit losses related to loans [member] | Canada [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Loans, Gross amount | 398,001 | 392,398
Loans, Net amount | 395,496 | 390,406
Allowance for credit losses related to loans [member] | Canada [member] | Related to impaired loans [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
ACL | 663 | 461
Allowance for credit losses related to loans [member] | Canada [member] | Related to performing loans [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
ACL | 1,842 | 1,531
Allowance for credit losses related to loans [member] | United States [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Loans, Gross amount | 272,996 | 277,718
Loans, Net amount | 270,482 | 275,385
Allowance for credit losses related to loans [member] | United States [member] | Related to impaired loans [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
ACL | 311 | 192
Allowance for credit losses related to loans [member] | United States [member] | Related to performing loans [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
ACL | 2,203 | 2,141
Allowance for credit losses related to loans [member] | Other countries [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Loans, Gross amount | 11,214 | 12,256
Loans, Net amount | 11,183 | 12,225
Allowance for credit losses related to loans [member] | Other countries [member] | Related to performing loans [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
ACL | $ 31 | $ 31

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- Definition Allowance for credit losses on financial assets. + References No definition available. + Details
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Balance Type: | credit
Period Type: | instant

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- Definition The amount of Retail and Wholesale loans made by the entity before allowance for loan losses. + References No definition available. + Details
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- Definition Loans net of allowance for credit losses. + References No definition available. + Details
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