Insurance Contracts - Analysis of Insurance Revenue (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Amounts relating to changes in liabilities for remaining coverage:
Amortization of insurance acquisition cash flows	$ (202)	$ (56)
Total insurance revenue for contracts not measured using the PAA	21,356	18,902
non-PAA
Amounts relating to changes in liabilities for remaining coverage:
Expected claims and other expenses	4,739	4,733
Release of risk adjustment	545	493
CSM recognized for services provided	923	871
Income taxes specifically chargeable to the policyholder	5	(71)
Premium experience adjustments	0	0
Amortization of insurance acquisition cash flows	202	57
Total insurance revenue for contracts not measured using the PAA	6,414	6,083
PAA
Amounts relating to changes in liabilities for remaining coverage:
Total insurance revenue for contracts not measured using the PAA	14,942	12,819
Reportable segments \| Canada
Amounts relating to changes in liabilities for remaining coverage:
Total insurance revenue for contracts not measured using the PAA	8,165	8,111
Reportable segments \| Canada \| non-PAA
Amounts relating to changes in liabilities for remaining coverage:
Expected claims and other expenses	2,924	2,785
Release of risk adjustment	344	339
CSM recognized for services provided	432	398
Income taxes specifically chargeable to the policyholder	5	(70)
Premium experience adjustments	0	0
Amortization of insurance acquisition cash flows	90	22
Total insurance revenue for contracts not measured using the PAA	3,795	3,474
Reportable segments \| Canada \| PAA
Amounts relating to changes in liabilities for remaining coverage:
Total insurance revenue for contracts not measured using the PAA	4,370	4,637
Reportable segments \| U.S.
Amounts relating to changes in liabilities for remaining coverage:
Total insurance revenue for contracts not measured using the PAA	11,721	9,004
Reportable segments \| U.S. \| non-PAA
Amounts relating to changes in liabilities for remaining coverage:
Expected claims and other expenses	1,092	803
Release of risk adjustment	32	27
CSM recognized for services provided	116	111
Income taxes specifically chargeable to the policyholder	0	0
Premium experience adjustments	0	0
Amortization of insurance acquisition cash flows	0	0
Total insurance revenue for contracts not measured using the PAA	1,240	941
Reportable segments \| U.S. \| PAA
Amounts relating to changes in liabilities for remaining coverage:
Total insurance revenue for contracts not measured using the PAA	10,481	8,063
Reportable segments \| Asia
Amounts relating to changes in liabilities for remaining coverage:
Total insurance revenue for contracts not measured using the PAA	1,385	1,323
Reportable segments \| Asia \| non-PAA
Amounts relating to changes in liabilities for remaining coverage:
Expected claims and other expenses	655	746
Release of risk adjustment	162	97
CSM recognized for services provided	365	326
Income taxes specifically chargeable to the policyholder	0	0
Premium experience adjustments	0	0
Amortization of insurance acquisition cash flows	112	35
Total insurance revenue for contracts not measured using the PAA	1,294	1,204
Reportable segments \| Asia \| PAA
Amounts relating to changes in liabilities for remaining coverage:
Total insurance revenue for contracts not measured using the PAA	91	119
Reportable segments \| Corporate
Amounts relating to changes in liabilities for remaining coverage:
Total insurance revenue for contracts not measured using the PAA	85	464
Reportable segments \| Corporate \| non-PAA
Amounts relating to changes in liabilities for remaining coverage:
Expected claims and other expenses	68	399
Release of risk adjustment	7	30
CSM recognized for services provided	10	36
Income taxes specifically chargeable to the policyholder	0	(1)
Premium experience adjustments	0	0
Amortization of insurance acquisition cash flows	0	0
Total insurance revenue for contracts not measured using the PAA	85	464
Reportable segments \| Corporate \| PAA
Amounts relating to changes in liabilities for remaining coverage:
Total insurance revenue for contracts not measured using the PAA	0	0
Consolidation adjustments
Amounts relating to changes in liabilities for remaining coverage:
Total insurance revenue for contracts not measured using the PAA	$ 0	$ 0

The increase (decrease) in insurance contracts liability (asset) resulting from amortisation of insurance acquisition cash flows. [Refer: Insurance contracts liability (asset); Increase (decrease) through insurance acquisition cash flows, insurance contracts liability (asset)]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 17
-IssueDate 2023-01-01
-Paragraph 103
-Subparagraph b
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=17&code=ifrs-tx-2023-en-r&anchor=para_103_b_ii&doctype=Standard
-URIDate 2023-03-23

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- Definition

The amount of revenue arising from the groups of insurance contracts issued. Insurance revenue shall depict the provision of services arising from the group of insurance contracts at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those services. [Refer: Insurance contracts issued [member]; Revenue]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 17
-IssueDate 2023-01-01
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 17
-IssueDate 2023-01-01
-Paragraph 106
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=17&code=ifrs-tx-2023-en-r&anchor=para_106&doctype=Standard
-URIDate 2023-03-23

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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-IssueDate 2023-01-01
-Paragraph 82
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-URIDate 2023-03-23

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- Definition

The amount of insurance revenue recognised in the period related to the change in the risk adjustment for non-financial risk, as specified in paragraph B124(b) of IFRS 17. [Refer: Insurance revenue; Risk adjustment for non-financial risk [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 17
-IssueDate 2023-01-01
-Paragraph 106
-Subparagraph a
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=17&code=ifrs-tx-2023-en-r&anchor=para_106_a_ii&doctype=Standard
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- Definition

The amount of insurance revenue recognised in the period related to the contractual service margin recognised in profit or loss because of the transfer of insurance contract services in the period, as specified in paragraph B124(c) of IFRS 17. [Refer: Insurance revenue; Contractual service margin [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 17
-IssueDate 2023-01-01
-Paragraph 106
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-URIDate 2023-03-23

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- Definition

Insurance revenue, adjustments for premiums

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- Definition

Insurance revenue, expected incurred claims and other insurance services expenses

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- Definition

Insurance revenue, income taxes chargeable to policyholder

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