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, 2024	Dec. 31, 2023
Changes in fair value measurement, assets [abstract]
Beginning balance	$ 162,948
Ending balance	178,698	$ 162,948
Fair value changes on investment properties	383	486
Amortization of leasing commissions and tenant inducements	72	34
Recurring fair value measurement \| Level 3
Changes in fair value measurement, assets [abstract]
Beginning balance	18,964	18,975
Included in net income	(157)	(571)
Included in OCI	5	4
Purchases / Issuances	2,254	2,231
Sales / Payments	(935)	(1,051)
Settlements	(109)	(20)
Transfers into Level 3	624	390
Transfers (out) of Level 3	(1,058)	(918)
Foreign currency translation	307	(76)
Ending balance	19,895	18,964
Gains (losses) included in earnings relating to instruments still held at the reporting date	(79)	(592)
Recurring fair value measurement \| Level 3 \| Previously stated
Changes in fair value measurement, assets [abstract]
Beginning balance	18,964
Ending balance		18,964
Recurring fair value measurement \| Level 3 \| Other financial invested assets
Changes in fair value measurement, assets [abstract]
Beginning balance	6,074	5,555
Included in net income	251	(169)
Included in OCI	0	0
Purchases / Issuances	825	984
Sales / Payments	(389)	(261)
Settlements	0	0
Transfers into Level 3	0	0
Transfers (out) of Level 3	(15)	0
Foreign currency translation	134	(35)
Ending balance	6,880	6,074
Gains (losses) included in earnings relating to instruments still held at the reporting date	247	(170)
Recurring fair value measurement \| Level 3 \| Other financial invested assets \| Previously stated
Changes in fair value measurement, assets [abstract]
Beginning balance	6,074
Ending balance		6,074
Recurring fair value measurement \| Level 3 \| Investment properties
Changes in fair value measurement, assets [abstract]
Beginning balance	9,723	10,102
Included in net income	(455)	(520)
Included in OCI	0	0
Purchases / Issuances	146	391
Sales / Payments	(255)	(220)
Settlements	0	0
Transfers into Level 3	0	0
Transfers (out) of Level 3	0	0
Foreign currency translation	131	(30)
Ending balance	9,290	9,723
Gains (losses) included in earnings relating to instruments still held at the reporting date	(369)	(522)
Recurring fair value measurement \| Level 3 \| Investment properties \| Previously stated
Changes in fair value measurement, assets [abstract]
Beginning balance	9,723
Ending balance		9,723
Recurring fair value measurement \| Level 3 \| Total invested assets measured at fair value
Changes in fair value measurement, assets [abstract]
Beginning balance	18,623	18,344
Included in net income	(149)	(556)
Included in OCI	5	4
Purchases / Issuances	2,081	2,058
Sales / Payments	(873)	(607)
Settlements	(108)	(19)
Transfers into Level 3	624	390
Transfers (out) of Level 3	(1,058)	(918)
Foreign currency translation	291	(73)
Ending balance	19,436	18,623
Gains (losses) included in earnings relating to instruments still held at the reporting date	(79)	(574)
Recurring fair value measurement \| Level 3 \| Total invested assets measured at fair value \| Previously stated
Changes in fair value measurement, assets [abstract]
Beginning balance	18,623
Ending balance		18,623
Recurring fair value measurement \| Level 3 \| Investments for account of segregated fund holders
Changes in fair value measurement, assets [abstract]
Beginning balance	341	631
Included in net income	(8)	(15)
Included in OCI	0	0
Purchases / Issuances	173	173
Sales / Payments	(62)	(444)
Settlements	(1)	(1)
Transfers into Level 3	0	0
Transfers (out) of Level 3	0	0
Foreign currency translation	16	(3)
Ending balance	459	341
Gains (losses) included in earnings relating to instruments still held at the reporting date	0	(18)
Recurring fair value measurement \| Level 3 \| Investments for account of segregated fund holders \| Previously stated
Changes in fair value measurement, assets [abstract]
Beginning balance	341
Ending balance		341
FVTPL \| Recurring fair value measurement \| Level 3 \| Debt securities
Changes in fair value measurement, assets [abstract]
Beginning balance	402	394
Included in net income	2	9
Included in OCI	0	0
Purchases / Issuances	436	211
Sales / Payments	(48)	(8)
Settlements	(37)	(6)
Transfers into Level 3	117	8
Transfers (out) of Level 3	(367)	(200)
Foreign currency translation	12	(6)
Ending balance	517	402
Gains (losses) included in earnings relating to instruments still held at the reporting date	(6)	5
FVTPL \| Recurring fair value measurement \| Level 3 \| Debt securities \| Previously stated
Changes in fair value measurement, assets [abstract]
Beginning balance	402
Ending balance		402
FVTPL \| Recurring fair value measurement \| Level 3 \| Equity securities
Changes in fair value measurement, assets [abstract]
Beginning balance	113	101
Included in net income	20	13
Included in OCI	0	0
Purchases / Issuances	77	18
Sales / Payments	(1)	(19)
Settlements	0	0
Transfers into Level 3	0	0
Transfers (out) of Level 3	0	0
Foreign currency translation	2	0
Ending balance	211	113
Gains (losses) included in earnings relating to instruments still held at the reporting date	19	9
FVTPL \| Recurring fair value measurement \| Level 3 \| Equity securities \| Previously stated
Changes in fair value measurement, assets [abstract]
Beginning balance	113
Ending balance		113
FVTPL \| Recurring fair value measurement \| Level 3 \| Mortgages and loans
Changes in fair value measurement, assets [abstract]
Beginning balance	2,056	2,054
Included in net income	33	119
Included in OCI	0	0
Purchases / Issuances	240	293
Sales / Payments	(133)	(75)
Settlements	(21)	(7)
Transfers into Level 3	439	382
Transfers (out) of Level 3	(320)	(710)
Foreign currency translation	6	0
Ending balance	2,300	2,056
Gains (losses) included in earnings relating to instruments still held at the reporting date	30	112
FVTPL \| Recurring fair value measurement \| Level 3 \| Mortgages and loans \| Previously stated
Changes in fair value measurement, assets [abstract]
Beginning balance	2,056
Ending balance		2,056
FVOCI \| Recurring fair value measurement \| Level 3 \| Debt securities
Changes in fair value measurement, assets [abstract]
Beginning balance	187	52
Included in net income	0	0
Included in OCI	5	3
Purchases / Issuances	335	153
Sales / Payments	(47)	(6)
Settlements	(50)	(6)
Transfers into Level 3	62	0
Transfers (out) of Level 3	(341)	(8)
Foreign currency translation	0	(1)
Ending balance	151	187
Gains (losses) included in earnings relating to instruments still held at the reporting date	0	0
FVOCI \| Recurring fair value measurement \| Level 3 \| Debt securities \| Previously stated
Changes in fair value measurement, assets [abstract]
Beginning balance	187
Ending balance		187
FVOCI \| Recurring fair value measurement \| Level 3 \| Equity securities
Changes in fair value measurement, assets [abstract]
Beginning balance	68	70
Included in net income	0	0
Included in OCI	0	0
Purchases / Issuances	0	0
Sales / Payments	0	(1)
Settlements	0	0
Transfers into Level 3	0	0
Transfers (out) of Level 3	0	0
Foreign currency translation	6	(1)
Ending balance	74	68
Gains (losses) included in earnings relating to instruments still held at the reporting date	0	0
FVOCI \| Recurring fair value measurement \| Level 3 \| Equity securities \| Previously stated
Changes in fair value measurement, assets [abstract]
Beginning balance	68
Ending balance		68
FVOCI \| Recurring fair value measurement \| Level 3 \| Mortgages and loans
Changes in fair value measurement, assets [abstract]
Beginning balance	0	16
Included in net income	0	(8)
Included in OCI	0	1
Purchases / Issuances	22	8
Sales / Payments	0	(17)
Settlements	0	0
Transfers into Level 3	6	0
Transfers (out) of Level 3	(15)	0
Foreign currency translation	0	0
Ending balance	13	0
Gains (losses) included in earnings relating to instruments still held at the reporting date	0	(8)
FVOCI \| Recurring fair value measurement \| Level 3 \| Mortgages and loans \| Previously stated
Changes in fair value measurement, assets [abstract]
Beginning balance	$ 0
Ending balance		$ 0

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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: Classes of financial instruments [domain]; Financial liabilities]

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The gains (losses) including exchange differences recognised in other comprehensive income on the fair value measurement of assets. [Refer: At fair value [member]; Other comprehensive income]

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

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The decrease in the fair value measurement of assets resulting from sales. [Refer: At fair value [member]]

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The decrease in the fair value measurement of assets resulting from settlements. [Refer: At fair value [member]]

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

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Amortization Of Leasing Commissions And Tenant Inducements

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Increase (Decrease) In Asset Fair Value, Investment Property

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