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Operating and Geographic Segmentation - Summary of Average Assets, Grouped by Operating Segment (Parenthetical) (Detail) - CAD ($) $ in Millions | 12 Months Ended
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Oct. 31, 2025 | Oct. 31, 2024
Disclosure of operating segments [line items] |  |
Average Earning Assets | $ 1,305,072 | $ 1,235,830
Canadian Personal and Commercial Banking [member] |  |
Disclosure of operating segments [line items] |  |
Average Earning Assets | 342,361 | 319,518
U.S. Banking [member] |  |
Disclosure of operating segments [line items] |  |
Average Earning Assets | 235,855 | 230,500
All Other Operating Segments [member] |  |
Disclosure of operating segments [line items] |  |
Average Earning Assets | $ 726,856 | $ 685,812

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Balance Type: | debit
Period Type: | duration

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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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- Details
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Namespace Prefix: |
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Period Type: |

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- Details
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Namespace Prefix: |
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Period Type: |

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- Details
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Namespace Prefix: |
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