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Goodwill and Intangible Assets - Summary of Intangible Assets (Detail) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Oct. 31, 2025 | Oct. 31, 2024
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | $ 4,925 |
Amortization | 1,152 | $ 1,112
Ending balance | 4,758 | 4,925
Customer-related intangible assets [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | 296 |
Ending balance | 213 | 296
Core deposit [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | 1,916 |
Ending balance | 1,626 | 1,916
Software amortizing [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | 2,006 |
Ending balance | 2,143 | 2,006
Software under development [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | 417 |
Ending balance | 532 | 417
Other intangible assets [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | 290 |
Ending balance | 244 | 290
Gross carrying amount [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | 11,516 | 12,370
Additions | 1,048 | 852
Fully amortized intangibles | (780) | (1,729)
Foreign exchange and other | 41 | 23
Ending balance | 11,825 | 11,516
Gross carrying amount [member] | Customer-related intangible assets [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | 852 | 850
Fully amortized intangibles | (16) |
Foreign exchange and other |  | 2
Ending balance | 836 | 852
Gross carrying amount [member] | Core deposit [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | 3,563 | 3,553
Foreign exchange and other | 28 | 10
Ending balance | 3,591 | 3,563
Gross carrying amount [member] | Software amortizing [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | 6,096 | 7,071
Additions | 71 | 22
Transfers | 821 | 688
Fully amortized intangibles | (673) | (1,696)
Foreign exchange and other | 12 | 11
Ending balance | 6,327 | 6,096
Gross carrying amount [member] | Software under development [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | 417 | 324
Additions | 938 | 782
Transfers | (821) | (688)
Foreign exchange and other | (2) | (1)
Ending balance | 532 | 417
Gross carrying amount [member] | Other intangible assets [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | 588 | 572
Additions | 39 | 48
Fully amortized intangibles | (91) | (33)
Foreign exchange and other | 3 | 1
Ending balance | 539 | 588
Accumulated depreciation and amortisation [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | (6,591) | (7,154)
Amortization | 1,152 | 1,112
Write-downs | 76 | 26
Fully amortized intangibles | (780) | (1,729)
Foreign exchange and other | 28 | 28
Ending balance | (7,067) | (6,591)
Accumulated depreciation and amortisation [member] | Customer-related intangible assets [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | (556) | (487)
Amortization | 70 | 62
Write-downs | 14 | 4
Fully amortized intangibles | (16) |
Foreign exchange and other | (1) | 3
Ending balance | (623) | (556)
Accumulated depreciation and amortisation [member] | Core deposit [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | (1,647) | (1,295)
Amortization | 305 | 342
Foreign exchange and other | 13 | 10
Ending balance | (1,965) | (1,647)
Accumulated depreciation and amortisation [member] | Software amortizing [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | (4,090) | (5,073)
Amortization | 739 | 676
Write-downs | 13 | 22
Fully amortized intangibles | (673) | (1,696)
Foreign exchange and other | 15 | 15
Ending balance | (4,184) | (4,090)
Accumulated depreciation and amortisation [member] | Other intangible assets [member] |  |
Disclosure of detailed information about intangible assets [line items] |  |
Beginning balance | (298) | (299)
Amortization | 38 | 32
Write-downs | 49 |
Fully amortized intangibles | (91) | (33)
Foreign exchange and other | 1 |
Ending balance | $ (295) | $ (298)

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