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Goodwill and Intangible Assets - Summary of Continuity of Goodwill By Group of CGUs (Detail) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Oct. 31, 2025 | Oct. 31, 2024
Disclosure Of Goodwill [Line Items] |  |
Beginning balance | $ 16,774 | $ 16,728
Write-downs | (102) |
Foreign exchange and other | 125 | 46
Ending balance | 16,797 | 16,774
Wealth management [member] |  |
Disclosure Of Goodwill [Line Items] |  |
Beginning balance | 260 | 260
Ending balance | 260 | 260
Capital markets [member] |  |
Disclosure Of Goodwill [Line Items] |  |
Beginning balance | 529 | 528
Foreign exchange and other | 3 | 1
Ending balance | 532 | 529
Wealth and Asset Management [member] | Wealth management [member] |  |
Disclosure Of Goodwill [Line Items] |  |
Beginning balance | 258 | 258
Ending balance | 258 | 258
Insurance products [member] | Wealth management [member] |  |
Disclosure Of Goodwill [Line Items] |  |
Beginning balance | 2 | 2
Ending balance | 2 | 2
Canada [member] | Personal and Commercial Banking [member] |  |
Disclosure Of Goodwill [Line Items] |  |
Beginning balance | 330 | 330
Ending balance | 330 | 330
United States [member] | U.S. Banking [member] |  |
Disclosure Of Goodwill [Line Items] |  |
Beginning balance | 15,655 | 15,610
Write-downs | (102) |
Foreign exchange and other | 122 | 45
Ending balance | $ 15,675 | $ 15,655

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