Goodwill and Intangible Assets - Goodwill Acquired by Segment (Details) - Goodwill - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Reconciliation of changes in intangible assets and goodwill [abstract]
Beginning balance	$ 6,517	$ 6,072
Acquisitions	2,030	479
Impairment	(170)
Foreign exchange rate movements	328	(34)
Ending balance	8,705	6,517
Disposal groups classified as held for sale \| Sun Life UK
Reconciliation of changes in intangible assets and goodwill [abstract]
Impairment	(170)
Canada
Reconciliation of changes in intangible assets and goodwill [abstract]
Beginning balance	2,607	2,607
Acquisitions	0	0
Impairment	0
Foreign exchange rate movements	0	0
Ending balance	2,607	2,607
U.S. (Employee Benefits)
Reconciliation of changes in intangible assets and goodwill [abstract]
Beginning balance	1,108	1,062
Acquisitions	2,030	53
Impairment	0
Foreign exchange rate movements	226	(7)
Ending balance	3,364	1,108
Asia
Reconciliation of changes in intangible assets and goodwill [abstract]
Beginning balance	659	665
Acquisitions	0	3
Impairment	0
Foreign exchange rate movements	41	(9)
Ending balance	700	659
Asset Management
Reconciliation of changes in intangible assets and goodwill [abstract]
Beginning balance	1,959	1,551
Acquisitions	0	423
Impairment	0
Foreign exchange rate movements	75	(15)
Ending balance	2,034	1,959
Corporate
Reconciliation of changes in intangible assets and goodwill [abstract]
Beginning balance	184	187
Acquisitions	0	0
Impairment	(170)
Foreign exchange rate movements	(14)	(3)
Ending balance	$ 0	$ 184

The increase in intangible assets and goodwill resulting from acquisitions through business combinations. [Refer: Business combinations [member]; Intangible assets and goodwill]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 38
-IssueDate 2022-03-24
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The amount of impairment loss recognised in profit or loss for intangible assets and goodwill. [Refer: Impairment loss recognised in profit or loss; Intangible assets and goodwill]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Number 38
-IssueDate 2022-03-24
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The amount of intangible assets and goodwill held by the entity. [Refer: Goodwill; Intangible assets other than goodwill]

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