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Other Liabilities - Additional Information (Detail) - CAD ($) $ in Millions	12 Months Ended
	Oct. 31, 2025	Oct. 31, 2024
Text Block [Line Items]
Interest expense on lease liabilities	$ 110	$ 110
Cash outflow for leases	426	455
Variable lease payments not included in the measurement of lease liabilities	276	$ 258
Year 2026 [member]
Text Block [Line Items]
Gross lease liabilities	468
Year 2027 [member]
Text Block [Line Items]
Gross lease liabilities	465
Year 2028 [member]
Text Block [Line Items]
Gross lease liabilities	436
Year 2029 [member]
Text Block [Line Items]
Gross lease liabilities	414
Year 2030 [member]
Text Block [Line Items]
Gross lease liabilities	390
Year 2031 and Thereafter [member]
Text Block [Line Items]
Gross lease liabilities	$ 1,756

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- Definition

The cash outflow for leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2024-01-01
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The amount of the expense relating to variable lease payments not included in the measurement of lease liabilities. Variable lease payments are the portion of payments made by a lessee to a lessor for the right to use an underlying asset during the lease term that varies because of changes in facts or circumstances occurring after the commencement date, other than the passage of time. [Refer: Lease liabilities]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The amount of contractual undiscounted cash flows in relation to lease liabilities before deducting finance charges. [Refer: Lease liabilities]

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The amount of interest expense on lease liabilities. [Refer: Lease liabilities]

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