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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
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

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- Definition

The amount of Retail and Wholesale loans made by the entity before allowance for loan losses.

+ References

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- Definition

Loans net of allowance for credit losses.

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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.

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