Total Invested Assets and Related Net Investment Income - Reconciliation of Assets and Liabilities Categorized in Level 3 (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Changes in fair value measurement, assets [abstract]
Beginning balance	$ 168,785
Ending balance	173,735	$ 168,785
Fair value and foreign currency changes on assets and liabilities	(1,785)	6,860
Fair value changes on investment properties	1,070	19
Recurring fair value measurement \| Level 3
Changes in fair value measurement, assets [abstract]
Beginning balance	11,231	10,821
Included in net income	1,456	(161)
Included in OCI	45	21
Purchases	1,960	1,383
Sales / Payments	(748)	(688)
Settlements	(24)	(27)
Transfers into Level 3		6
Transfers (out) of Level 3	(140)	(90)
Foreign currency translation	(35)	(34)
Ending balance	13,745	11,231
Fair value and foreign currency changes on assets and liabilities	1,459	(76)
Recurring fair value measurement \| Other invested assets \| Level 3
Changes in fair value measurement, assets [abstract]
Beginning balance	2,645	2,445
Included in net income	392	(87)
Included in OCI	13	19
Purchases	1,074	594
Sales / Payments	(469)	(304)
Settlements	0	0
Transfers into Level 3		0
Transfers (out) of Level 3	0	0
Foreign currency translation	(5)	(22)
Ending balance	3,650	2,645
Fair value and foreign currency changes on assets and liabilities	382	(68)
Recurring fair value measurement \| Investment properties \| Level 3
Changes in fair value measurement, assets [abstract]
Beginning balance	7,516	7,306
Included in net income	1,032	(63)
Included in OCI	0	0
Purchases	764	620
Sales / Payments	(197)	(325)
Settlements	0	0
Transfers into Level 3		0
Transfers (out) of Level 3	0	0
Foreign currency translation	(6)	(22)
Ending balance	9,109	7,516
Fair value and foreign currency changes on assets and liabilities	1,038	13
Recurring fair value measurement \| Total invested assets measured at fair value \| Level 3
Changes in fair value measurement, assets [abstract]
Beginning balance	10,681	10,272
Included in net income	1,433	(139)
Included in OCI	45	21
Purchases	1,895	1,353
Sales / Payments	(739)	(674)
Settlements	(23)	(26)
Transfers into Level 3		5
Transfers (out) of Level 3	(140)	(89)
Foreign currency translation	(18)	(42)
Ending balance	13,134	10,681
Fair value and foreign currency changes on assets and liabilities	1,432	(53)
Recurring fair value measurement \| Investments for account of segregated fund holders \| Level 3
Changes in fair value measurement, assets [abstract]
Beginning balance	550	549
Included in net income	23	(22)
Included in OCI	0	0
Purchases	65	30
Sales / Payments	(9)	(14)
Settlements	(1)	(1)
Transfers into Level 3		1
Transfers (out) of Level 3	0	(1)
Foreign currency translation	(17)	8
Ending balance	611	550
Fair value and foreign currency changes on assets and liabilities	27	(23)
Fair value through profit or loss \| Recurring fair value measurement \| Debt securities \| Level 3
Changes in fair value measurement, assets [abstract]
Beginning balance	225	248
Included in net income	(6)	11
Included in OCI	0	0
Purchases	29	67
Sales / Payments	(9)	(10)
Settlements	(15)	(9)
Transfers into Level 3		3
Transfers (out) of Level 3	(57)	(88)
Foreign currency translation	(5)	3
Ending balance	162	225
Fair value and foreign currency changes on assets and liabilities	(4)	2
Fair value through profit or loss \| Recurring fair value measurement \| Equity securities \| Level 3
Changes in fair value measurement, assets [abstract]
Beginning balance	181	188
Included in net income	10	0
Included in OCI	0	0
Purchases	8	11
Sales / Payments	(25)	(2)
Settlements	(5)	(15)
Transfers into Level 3		0
Transfers (out) of Level 3	(73)	0
Foreign currency translation	0	(1)
Ending balance	96	181
Fair value and foreign currency changes on assets and liabilities	11	0
Available- for-sale \| Recurring fair value measurement \| Debt securities \| Level 3
Changes in fair value measurement, assets [abstract]
Beginning balance	67	50
Included in net income	0	0
Included in OCI	(1)	2
Purchases	5	15
Sales / Payments	(13)	0
Settlements	(3)	(2)
Transfers into Level 3		2
Transfers (out) of Level 3	(10)	(1)
Foreign currency translation	(2)	1
Ending balance	43	67
Fair value and foreign currency changes on assets and liabilities	0	0
Available- for-sale \| Recurring fair value measurement \| Equity securities \| Level 3
Changes in fair value measurement, assets [abstract]
Beginning balance	47	35
Included in net income	5	0
Included in OCI	33	0
Purchases	15	46
Sales / Payments	(26)	(33)
Settlements	0	0
Transfers into Level 3		0
Transfers (out) of Level 3	0	0
Foreign currency translation	0	(1)
Ending balance	74	47
Fair value and foreign currency changes on assets and liabilities	5	0
Leasing commissions and tenant inducements
Changes in fair value measurement, assets [abstract]
Fair value changes on investment properties	$ 38	$ 82

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The amount of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Financial instruments, class [member]; Financial liabilities]

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The gains (losses) recognised in profit or loss for assets measured at fair value that are attributable to the change in unrealised gains or losses relating to those assets held at the end of the reporting period. [Refer: At fair value [member]]

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The gains (losses) including exchange differences recognised in profit or loss on the fair value measurement of assets. [Refer: At fair value [member]]

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The amount of transfers of assets out of Level 3 of the fair value hierarchy. [Refer: Level 3 of fair value hierarchy [member]]

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