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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 |

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- Definition The amount of an allowance account used to record impairments to off balance sheet due to credit losses. + References No definition available. + Details
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Period Type: | instant

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- Definition Allowance for credit losses on financial assets. + References No definition available. + Details
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- 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 Renegotiated loans. + 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 -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_35J_b&doctype=Standard -URIDate 2024-03-27 + Details
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- 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 -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 112 -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_112_c&doctype=Standard -URIDate 2024-03-27 + Details
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