Securities - Additional Information (Detail) - CAD ($) $ in Millions	3 Months Ended	9 Months Ended
Jul. 31, 2024	Apr. 30, 2024	Jul. 31, 2023	Jul. 31, 2024	Jul. 31, 2023
Disclosure of financial assets [line items]
Fair value of equity securities designated at FVOCI that were disposed			$ 5		$ 10
Net realized cumulative after-tax gains (loss) reclassifed from AOCI to retained earnings	(19)		2	(18)	4
Dividend income recognized on equity securities	1		1	2	3
Dividend income recognized on equity securities designated at FVOCI that were disposed

Fair value of investments in equity instruments measured at fair value through other comprehensive income disposed.

No definition available.

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- Definition

The cumulative gain (loss) on disposal of investments in equity instruments that the entity has designated at fair value through other comprehensive income. [Refer: At fair value [member]; Other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 11B
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_11B_c&doctype=Standard
-URIDate 2023-03-23

+ Details

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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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- Definition

The amount of dividends related to investments in equity instruments that the entity has designated at fair value through other comprehensive income, derecognised during the reporting period. [Refer: Investments in equity instruments designated at fair value through other comprehensive income [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 11A
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_11A_d&doctype=Standard
-URIDate 2023-03-23

+ Details

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- Definition

The amount of dividends related to investments in equity instruments that the entity has designated at fair value through other comprehensive income, held at the end of the reporting period. [Refer: Investments in equity instruments designated at fair value through other comprehensive income [member]]

+ References

+ Details

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