Schedule IV Reinsurance (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Life insurance in-force
Gross Amount	$ 1,301,304	$ 1,275,984	$ 1,147,723
Ceded Amount	35,266	33,009	23,330
Assumed From Other Companies	25,362	23,605	22,511
Net Amount	$ 1,291,400	$ 1,266,580	$ 1,146,904
Percentage of Amount Assumed to Net	2.00%	2.00%	2.00%
Insurance revenues
Gross Amount	$ 23,491	$ 21,959	$ 20,316
Ceded Amount	1,869	1,716	1,568
Assumed From Other Companies	1,167	1,000	829
Premiums Earned, Net	$ 22,567	$ 21,026	$ 19,390
Percentage of Amount Assumed to Net	5.00%	5.00%	4.00%
Earned premiums and fees [Member]
Insurance revenues
Premiums Earned, Net	$ 22,789	$ 21,243	$ 19,577
Property and Casualty Insurance Products
Insurance revenues
Gross Amount	16,915	15,514	14,328
Ceded Amount	1,742	1,612	1,462
Assumed From Other Companies	1,001	826	654
Premiums Earned, Net	$ 16,174	$ 14,728	$ 13,520
Percentage of Amount Assumed to Net	6.00%	6.00%	5.00%
Life insurance and annuities
Insurance revenues
Gross Amount	$ 2,582	$ 2,540	$ 2,341
Ceded Amount	41	33	25
Assumed From Other Companies	76	76	77
Premiums Earned, Net	$ 2,617	$ 2,583	$ 2,393
Percentage of Amount Assumed to Net	3.00%	3.00%	3.00%
Accident and health insurance
Insurance revenues
Gross Amount	$ 3,994	$ 3,905	$ 3,647
Ceded Amount	86	71	81
Assumed From Other Companies	90	98	98
Premiums Earned, Net	$ 3,998	$ 3,932	$ 3,664
Percentage of Amount Assumed to Net	2.00%	2.00%	3.00%

Amount of life insurance issued and outstanding assumed from other entity, as disclosed in supplementary reinsurance information. Includes, but is not limited to, dividend and adjustment to face value.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 17
-Paragraph Column D
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column D))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477965/944-235-S99-2

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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