Financial Instruments - Reconciliation of Changes in the Fair Value of Available for Sale Financial Assets (Detail) - Level 3 of fair value hierarchy $ in Millions	9 Months Ended
Sep. 30, 2023 CAD ($)
Disclosure of fair value measurement of assets [Line Items]
Fair value, beginning of year	$ 55
Acquisition	11
Fair value, end of year	$ 66

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.

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfFairValueMeasurementOfAssetsLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The fair value of financial assets. [Refer: At fair value [member]; Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 25
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_25&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_FinancialAssetsAtFairValue
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The increase in the fair value measurement of assets resulting from purchases of those assets. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2023-01-01
-Paragraph 93
-Subparagraph e
-Clause iii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=13&code=ifrs-tx-2023-en-r&anchor=para_93_e_iii&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_PurchasesFairValueMeasurementAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	ifrs-full_LevelsOfFairValueHierarchyAxis=ifrs-full_Level3OfFairValueHierarchyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: