Invested Assets and Investment Income - Summary of Rental Income of Investment Properties (Detail) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Disclosure of detailed information about investment property [abstract]
Rental income from investment properties	$ 874	$ 864
Direct operating expenses of rental investment properties	(491)	(464)
Total	$ 383	$ 400

The amount of direct operating expenses (including repairs and maintenance) arising from investment property that generated rental income during the period recognised in profit or loss. [Refer: Investment property]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2020-01-01
-Paragraph 75
-Subparagraph f
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=40&code=ifrs-tx-2020-en-r&anchor=para_75_f_ii&doctype=Standard
-URIDate 2020-01-01

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Period Type:	duration

- References

No definition available.

+ Details

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- Definition

The amount of rental income arising from investment property recognised in profit or loss. [Refer: Investment property]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2020-01-01
-Paragraph 75
-Subparagraph f
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=40&code=ifrs-tx-2020-en-r&anchor=para_75_f_i&doctype=Standard
-URIDate 2020-01-01

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Balance Type:	credit
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- Definition

The amount of rental income arising from investment property, net of direct operating expense from such property. [Refer: Direct operating expense from investment property; Rental income from investment property]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2020-01-01

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