Loans and Allowance for Credit Losses - Additional Information (Detail) - CAD ($) $ in Millions	12 Months Ended
Oct. 31, 2025	Oct. 31, 2024
Disclosure of detailed information about financial instruments [line items]
Interest income on impaired loans	$ 358	$ 306
Allowances for credit losses	5,739	4,936
Carrying value of renegotiated loans	2,606	1,595
Real estate properties held for sale	$ 52	67
Base case scenario [member]
Disclosure of detailed information about financial instruments [line items]
Scenario weight	100.00%
Severe Downside Scenario [member]
Disclosure of detailed information about financial instruments [line items]
Scenario weight	100.00%
12-month expected credit losses [member]
Disclosure of detailed information about financial instruments [line items]
Modified loss allowance during the year change from lifetime to 12-month ECL.	$ 2	3
Allowance for credit losses related to loans [member]
Disclosure of detailed information about financial instruments [line items]
Allowances for credit losses	5,050	4,356
Allowance for credit losses related to other credit instruments [member]
Disclosure of detailed information about financial instruments [line items]
Allowances for credit losses off balance sheet	689	580
Related to performing loans, assuming 100% base case scenario [member]
Disclosure of detailed information about financial instruments [line items]
Allowances for credit losses	4,709	4,205
Modelled allowance account for credit losses of financial assets based on assumptions	3,125	2,625
Related to performing loans, assuming 100% severe downside scenario [member]
Disclosure of detailed information about financial instruments [line items]
Allowances for credit losses	4,709	4,205
Modelled allowance account for credit losses of financial assets based on assumptions	7,975	7,500
Performing loans, stage one scenario [member]
Disclosure of detailed information about financial instruments [line items]
Allowances for credit losses	4,709	4,205
Modelled allowance account for credit losses of financial assets based on assumptions	$ 3,375	$ 3,050
Expected credit loss period	12 months

The amount of an allowance account used to record impairments to off balance sheet due to credit losses.

No definition available.

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Period Type:	instant

- Definition

Allowance for credit losses on financial assets.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Expected credit loss period.

+ References

No definition available.

+ Details

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- Definition

Modelled allowance account for credit losses of financial assets based on assumptions

+ References

No definition available.

+ Details

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- Definition

Real estate properties held for sale

+ References

No definition available.

+ Details

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- Definition

Renegotiated loans.

+ References

No definition available.

+ Details

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- Definition

ScenarioWeighting.

+ 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 gross carrying amount of financial assets that have been modified since initial recognition at a time when the loss allowance was measured at an amount equal to lifetime expected credit losses and for which the loss allowance has changed during the reporting period to an amount equal to 12-month expected credit losses. [Refer: Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 35J
-Subparagraph b
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-URIDate 2024-03-27

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of interest income on other financial assets. [Refer: Interest income; Other financial assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-IssueDate 2024-01-01
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- Details

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- Details

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