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v3.25.3

Fair Value Measurements and Trading-Related Revenue - Significant Unobservable Inputs in Level 3 Instrument Valuations (Detail) - Valued using models (without observable inputs) [member] $ in Millions | 12 Months Ended
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Oct. 31, 2025 CAD ($) Range | Oct. 31, 2024 CAD ($) Range
Corporate equity [member] |  |
Disclosure Of Fair Value Of Financial Instruments [Line Items] |  |
Fair value of assets | $ 6,016 | $ 4,899
Corporate equity [member] | Bottom of range [member] |  |
Disclosure Of Fair Value Of Financial Instruments [Line Items] |  |
EV/EBITDA multiple range of input values | Range | 5 | 5
Changes in fair value from using reasonably possible alternatives | $ (38) | $ (18)
Corporate equity [member] | Top of range [member] |  |
Disclosure Of Fair Value Of Financial Instruments [Line Items] |  |
EV/EBITDA multiple range of input values | Range | 28 | 21
Changes in fair value from using reasonably possible alternatives | $ 38 | $ 18
Other assets [member] |  |
Disclosure Of Fair Value Of Financial Instruments [Line Items] |  |
Fair value of assets | $ 1,396 | $ 1,363
Other assets [member] | Bottom of range [member] |  |
Disclosure Of Fair Value Of Financial Instruments [Line Items] |  |
Discounted cash flows and capitalization rate changes in percentage | 5.00% | 2.00%
Changes in fair value from using reasonably possible alternatives | $ (108) | $ (118)
Other assets [member] | Top of range [member] |  |
Disclosure Of Fair Value Of Financial Instruments [Line Items] |  |
Discounted cash flows and capitalization rate changes in percentage | 7.00% | 8.00%
Changes in fair value from using reasonably possible alternatives | $ 128 | $ 151

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- Definition The fair value of financial assets. [Refer: At fair value [member]; Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 25 -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_25&doctype=Standard -URIDate 2024-03-27 + Details
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