Insurance - Summary of Insurance Service Results (Detail) - CAD ($) $ in Millions	3 Months Ended
Jan. 31, 2025	Oct. 31, 2024	Jan. 31, 2024
Disclosure in tabular form of insurance service result [line items]
Insurance revenue	$ 470		$ 433
Insurance service expenses	(351)		(297)
Net expenses from reinsurance contracts	(28)		(37)
Insurance service results	$ 91	$ 42	$ 99

Disclosure in tabular form of insurance service result.

No definition available.

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- Definition

The amount of income (expenses) from a group of reinsurance contracts held, other than finance income (expenses). [Refer: Reinsurance contracts held [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 17
-IssueDate 2024-01-01
-Paragraph 86
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=17&code=ifrs-tx-2024-en-r&anchor=para_86&doctype=Standard
-URIDate 2024-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
-Paragraph 82
-Subparagraph ac
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_82_ac&doctype=Standard
-URIDate 2024-03-27

+ Details

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- Definition

The amount of revenue arising from the groups of insurance contracts issued. Insurance revenue shall depict the provision of services arising from the group of insurance contracts at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those services. [Refer: Insurance contracts issued [member]; Revenue]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 17
-IssueDate 2024-01-01
-Paragraph 80
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=17&code=ifrs-tx-2024-en-r&anchor=para_80_a&doctype=Standard
-URIDate 2024-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 17
-IssueDate 2024-01-01
-Paragraph 106
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=17&code=ifrs-tx-2024-en-r&anchor=para_106&doctype=Standard
-URIDate 2024-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
-Paragraph 82
-Subparagraph a
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_82_a_ii&doctype=Standard
-URIDate 2024-03-27

+ Details

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- Definition

The amount of expenses arising from a group of insurance contracts issued, comprising incurred claims (excluding repayments of investment components), other incurred insurance service expenses, amortisation of insurance acquisition cash flows, changes that relate to past service and changes that relate to future service. [Refer: Insurance contracts issued [member]]

+ References

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- Definition

The amount comprising insurance revenue and insurance service expenses. [Refer: Insurance revenue; Insurance service expenses from insurance contracts issued; Income (expenses) from reinsurance contracts held, other than finance income (expenses)]

+ References

+ Details

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